Is Your Service Taxable in Connecticut? The 6.35% Rule, the 1% Computer Services Rate, and What Hartford Firms Must Collect

Connecticut sales tax on services applies only to services the state specifically identifies as taxable, not to every service a business sells. Most taxable services use the 6.35% statewide rate, while qualifying computer and data-processing services are taxed at 1%. A seller with a Connecticut collection obligation generally must register, collect, file, and remit the tax.

That sounds straightforward until a Hartford consulting firm sells software implementation, a SaaS company bundles support with platform access, or an IT provider combines help desk work, cybersecurity monitoring, cloud backup, and advisory services on one invoice.

Connecticut’s rules require a classification exercise before a billing-system exercise. The service must first be identified, matched to a statutory taxable category, assigned the correct rate, sourced to Connecticut, and tested for any valid resale or exemption treatment. Only then should the seller configure a tax code or begin charging customers.

The current Connecticut Department of Revenue Services list of taxable services is available through its official Services Subject to Sales and Use Taxes guidance. DRS also maintains current rate, registration, filing, and permit information on its Sales and Use Tax Information page.

Connecticut Service Sales Tax Quick Reference

• Regular taxable-service rate: 6.35%
• Computer/data-processing treatment: 1% for qualifying computer and data-processing services; electronically accessed or transferred canned software bought by a business for business use is also listed at 1%
• Non-taxable services: Services outside Connecticut’s taxable-service categories, subject to the exact facts and any bundled taxable components
• Registration: Required when a seller has an obligation to collect Connecticut sales and use tax
• Permit fee: $100
• B2B: Business-to-business status does not automatically make a sale exempt
• Resale/exemption: A valid statutory basis and appropriate documentation are required
• Returns: Form OS-114 is filed electronically through myconneCT on the frequency assigned by DRS
• Audit exposure: A seller can remain liable for tax that should have been collected but was not

Connecticut Sales Tax on Services: Which Services Are Actually Taxable?

Connecticut does not automatically tax every activity that can be described as a service. Section 12-407 specifically enumerates taxable services, and the Connecticut Department of Revenue Services maintains a current list of services subject to Connecticut sales and use tax that businesses can use as the starting point for classification.

That means the question is not merely, “Did we provide labor?” Nor is it, “Are we a consulting company?” The meaningful question is whether the actual work sold fits one of Connecticut’s taxable categories.

A Hartford company can therefore have multiple tax treatments inside the same legal entity. A technology firm might sell taxable computer/data-processing services, taxable business-management consulting, non-taxable advisory work that does not fall within an enumerated category, and tangible hardware subject to a different rule.

Which services are taxable in Connecticut?

Connecticut taxes specifically enumerated services. Current DRS guidance lists, among others, computer and data processing, business analysis and management consulting, advertising or public-relations services in specified circumstances, employment and personnel services, janitorial services, certain repair and maintenance services, telecommunications, private investigation/security, health and athletic club services, credit reporting, lobbying, and several property-related or personal-service categories.

Most of those taxable services fall under the general 6.35% rate unless a special rate applies. Qualifying computer and data-processing services are a major exception and are currently taxed at 1%.

Taxable Services Connecticut List: The Categories Businesses Commonly Miss

A practical taxable services Connecticut list should be used as a classification starting point, not as a substitute for reading the statute or DRS guidance. The same invoice label can produce different results depending on what was actually delivered.

Service Category	Taxable?	Current Rate	Key Caveat
Business analysis / management / management consulting	Yes, when within the statutory category	6.35%	“Consulting” is not automatically exempt
Computer and data processing	Yes	1%	Classification must actually fit the computer/data category
Website creation, development, hosting, maintenance	Listed by current DRS as computer/data processing	1%	Separate non-computer work may require its own analysis
Electronically accessed canned software purchased by a business for business use	Yes	1%	Personal use is generally 6.35%
Canned software transferred with tangible personal property	Yes	6.35%	Delivery method matters
Advertising/public relations services described by DRS	Yes	Generally 6.35%	Statutory exclusions and media-advertising distinctions matter
Employment/personnel services	Yes	6.35%	Applies to covered agency/personnel services
Janitorial services	Yes	6.35%	Confirm exact scope
Maintenance/repair to tangible personal property	Yes in listed categories	6.35%	Property and service type matter
Private investigation/security services	Yes, subject to listed exclusions	6.35%	DRS lists specific exclusions
Telecommunications services	Yes	Category-specific tax rules apply	Telecom has separate sourcing and fee issues
Legal services	Generally outside the enumerated taxable-service list	0% if no taxable component applies	Ancillary taxable services can change the result
Accounting services	Generally outside the enumerated list	0% if no taxable component applies	Do not confuse accounting with taxable business-management consulting
Professional advisory services not otherwise enumerated	Potentially outside tax	Depends on actual service	Labels alone do not control

The DRS list is broad. It includes business analysis, management, management consulting, advertising/public relations, personnel services, credit information, maintenance services, telecommunications, lobbying, private investigation/security, janitorial services, website-related computer services, and other categories.

This is why a professional-services firm should not assume that a sophisticated B2B engagement is exempt merely because the invoice says “advisory fee.”

Which categories do Hartford firms commonly miss?

Management consulting is one of the most important. A firm may think of itself as a strategy consultant or operational adviser, but Connecticut specifically includes business analysis, management, and management consulting in the taxable-service list.

Technology engagements are another source of error. Software installation, support, custom development, data access, website work, and SaaS may fall within the computer/data-processing rules instead of the standard 6.35% rate.

Advertising and public-relations work can also be misunderstood. DRS identifies specified advertising or public-relations services as taxable, but the statute and administrative rules distinguish certain media-advertising activity. That makes scope-of-work wording and deliverables significant.

Professional services that are generally outside the enumerated list

Connecticut does not publish a master “exempt professional services” list in the same way it publishes taxable categories. Instead, services that do not fit an enumerated taxable category generally remain outside sales tax.

Legal and ordinary accounting services are common examples of professional services that are not themselves listed in the current DRS taxable-service summary. That does not mean every charge by a law firm or CPA firm is automatically non-taxable.

A CPA firm that separately resells taxable software access, for example, may have a taxable charge even though the firm’s core accounting work remains outside the enumerated list. A consulting firm may also cross into taxable management consulting depending on what it actually does.

6.35% vs the Computer and Data Processing Rate

Connecticut’s general sales-and-use-tax rate remains 6.35%, while qualifying computer and data-processing services use a special 1% rate. The current Connecticut sales-and-use-tax rates and filing guidance also confirms that Connecticut does not impose an additional local sales tax in Hartford or other municipalities.

That distinction is central to Connecticut sales tax on services because applying 6.35% to every taxable service can be just as wrong as charging nothing.

Service Type	Rate	Example	Key Caveat
Enumerated taxable service using general rate	6.35%	Covered management consulting	Confirm no special rule applies
Computer/data processing	1%	Qualifying data-processing or software-support work	Must fit the statutory category
Electronically accessed canned software for business use	1%	Business-use online software	Personal use has different treatment
Electronically accessed canned software for personal use	6.35%	Consumer software access	Purchaser use matters
Canned software delivered with tangible media/property	6.35%	Software supplied on tangible medium	Delivery method matters
Non-taxable professional service	No Connecticut sales tax if truly outside taxable categories	Ordinary accounting engagement	Bundled taxable elements may change result

1% Computer and Data Processing Tax CT: How the Rule Works

The phrase 1% computer and data processing tax CT describes a real current Connecticut rate, but it should not be applied to every IT invoice.

Current DRS guidance says sales of computer and data-processing services are taxed at 1%. It also places electronically accessed or electronically transferred canned software purchased by a business for business use at that rate.

Connecticut administrative guidance has historically described computer/data-processing services broadly enough to include computer time, storing and filing information, retrieving or providing access to information, custom software creation, software installation, software maintenance, software support, and related computer services. 

Current DRS guidance also expressly lists website creation, development, hosting, and maintenance in the category. The rate therefore turns on classification, not on whether the provider has “IT” in its name.

What is Connecticut’s tax rate on services?

There is no single rate for every service. Most Connecticut taxable services use the 6.35% general rate. Qualifying computer and data-processing services use a 1% rate, and certain electronically accessed or transferred canned software purchased for business use also falls under the 1% treatment. Services outside the enumerated taxable categories generally are not subject to Connecticut sales tax.

SaaS, Software, Managed IT, and Consulting: Where the Lines Get Difficult

Technology sellers should resist two shortcuts: “all SaaS is 1%” and “all IT is computer processing.”

Both can produce incorrect results.

Offering	Likely Category to Analyze	Rate if Category Applies	What to Verify
Hosted SaaS used by a business	Computer/data processing or business-use electronically accessed software	Often 1%	Function, access, purchaser use
Digital-content subscription	Computer/data processing	1% in DRS ruling	Customer location/use
Custom software development	Computer/data processing	1%	Whether truly custom
Software installation	Computer/data processing	1%	Separately stated scope
Software maintenance/support	Computer/data processing	1%	Support tied to software
Website development	Computer/data processing under current DRS listing	1%	Distinguish other creative/marketing services
Website hosting/maintenance	Computer/data processing	1%	Confirm service supplied
Managed IT help desk	Often computer/data processing	1% if category applies	Determine whether service is technical support versus other consulting
Management/strategy consulting	Business-management consulting	6.35%	Avoid misclassifying as IT merely because technology is discussed
Hardware repair	Repair/maintenance service	Generally 6.35%	Hardware and labor components
Advertising/PR services	Enumerated category in specified situations	Generally 6.35%	Media-advertising exceptions and scope

Is SaaS taxable in Connecticut?

SaaS tax Connecticut analysis depends on what the customer is buying and how the service fits Connecticut’s computer/data-processing and software rules. 

DRS has ruled that subscriptions providing online access to digital content can be taxable as computer/data-processing services, and current guidance taxes electronically accessed canned software bought by a business for business use at 1%.

A SaaS seller should document whether its charge is for prewritten software access, data access, processing, hosting, support, consulting, or a combination. A national tax engine’s default classification should not replace that analysis.

Custom software versus standard software

Connecticut distinguishes custom software from canned or prewritten software.

DRS guidance describes custom software as a program prepared to the special order of a single customer. Development, adaptation, installation, maintenance, and related services can fall within the computer/data-processing category.

Prewritten software requires separate attention. Current DRS rules distinguish electronically accessed business-use software, personal-use software, and software delivered with tangible personal property.

Managed IT services

Managed-service providers frequently bill one monthly amount for:

• remote monitoring;
• help desk;
• cybersecurity tools;
• cloud backup;
• software management;
• patching;
• endpoint support;
• hardware support;
• technology road-mapping;
• compliance advisory work.

That invoice should not be classified based on its title alone.

The technical components may fit computer and data processing. Hardware repair may fall under taxable repair or maintenance rules. High-level management or business consulting may be taxable at 6.35% under a different category.

A bundle therefore needs a “true object” and component analysis rather than automatic assignment to the lowest or highest possible rate. Connecticut rulings have long used the substance of the transaction and the role of the computer service in evaluating computer/data-processing treatment.

Consulting bundled with taxable computer services

A contract might include discovery workshops, implementation, software configuration, user training, support, and executive advisory work.

Separately stating a charge can help preserve accurate records, but invoice separation by itself does not create a tax exemption. The contractual scope must reflect real, distinct services.

Website development

Current DRS taxable-services guidance specifically includes services to create, develop, host, or maintain all or part of a website within computer and data-processing services.

That matters because some older Connecticut policy statements contained an exclusion for website creation and maintenance. Current DRS public guidance now points in the opposite direction and should be the operational starting point for 2026 compliance.

A marketing/technology agency should still separate website coding and hosting from unrelated campaign strategy, media buying, branding, or other services that may fall under different statutory rules.

Data processing versus data creation

Connecticut computer/data-processing rules historically focus on activities such as storing, filing, retrieving, processing, or providing access to information. That differs from paying a professional to originate an independent analysis or creative work where the computer is merely incidental.

One older Connecticut ruling explains the distinction through the “true object” concept: use of a computer does not by itself turn the entire service into computer/data processing if the technology is merely incidental to the service being purchased.

Mixed Contracts: Tax the Actual Components, Not the Invoice Title

Mixed contracts are where operational tax errors often begin.

Consider a Hartford technology project containing:

• $20,000 advisory work;
• $30,000 software implementation;
• $10,000 prewritten software;
• $5,000 hardware;
• $3,000 reimbursed travel and third-party costs.

Each line may require a different analysis.

The seller should determine which amounts are taxable services, which qualify for the 1% computer/data-processing treatment, which constitute tangible personal property, and whether any reimbursed expense becomes part of taxable gross receipts.

Do not assume a reimbursement is outside the taxable base merely because it appears below the service fee. Likewise, do not assume a taxable software component disappears because it is embedded in a larger consulting contract.

A disciplined engagement file should contain:

1. the signed contract;
2. statement of work;
3. service descriptions;
4. product/SKU tax code;
5. customer location;
6. resale/exemption documentation;
7. invoice;
8. payment record;
9. credit/refund history.

For professional-service firms, the billing workflow should keep earned fees, tax collected, processor charges, refunds, and settlement amounts in distinct accounting fields. 

A structured approach to professional-services invoices, ACH payments, client payment records, and settlement reconciliation makes it easier to trace what the customer owed, what was collected as tax, and what actually reached the bank.

Connecticut Service Business Sales Tax Registration

Connecticut service business sales tax registration becomes relevant once the seller has taxable Connecticut sales and an obligation to collect.

Connecticut-based sellers that make taxable service sales must generally register with DRS. Current DRS guidance says sellers of taxable services must obtain a Sales and Use Tax Permit, and the permit must be obtained before making taxable sales. The current registration fee is $100.

The permit is not limited to retail stores. Service firms, SaaS sellers, consultants selling taxable management services, IT businesses, and other taxable-service providers can need one.

Remote sellers and economic nexus

An out-of-state seller must register when it makes retail sales of tangible personal property or services to Connecticut destinations and, during the applicable 12-month measuring period ending September 30, has 200 or more Connecticut retail sales and at least $100,000 in Connecticut gross receipts. 

DRS also identifies physical-presence situations that can create registration obligations below that threshold.

Remote sellers therefore need two separate analyses:

• taxability: Is the service taxable?
• nexus: Is the seller required to collect?

A taxable service does not create collection liability in every interstate scenario if the seller lacks a Connecticut collection obligation. Conversely, a remote seller that meets Connecticut’s rules cannot ignore tax because it has no Connecticut office.

Sourcing of services

For computer/data-processing services, Connecticut rulings have stated that the service is taxable where it is delivered or intended for use, including where the benefit is received in Connecticut.

Multi-state contracts need more care. A SaaS subscription used by employees in several states, a consulting project benefiting several offices, or a centralized IT service can require allocation or sourcing analysis based on the governing Connecticut rules and facts.

Do not source a service solely from the customer’s billing address if the actual benefit or intended use occurs elsewhere.

How to Get a CT Sales Tax Permit

A CT sales tax permit is obtained through myconneCT, the Connecticut Department of Revenue Services online portal. New businesses complete the electronic REG-1 registration process, select the applicable tax types, pay the $100 sales-and-use-tax registration fee, and can access the permit once registration is processed.

A practical Connecticut service business sales tax registration workflow is:

1. Identify each service sold.
2. Determine whether the service is taxable.
3. Determine the applicable rate.
4. Confirm Connecticut sourcing.
5. Confirm physical or economic nexus.
6. Create or access a myconneCT account.
7. Complete the electronic REG-1 registration.
8. Register for sales and use tax.
9. Pay the $100 fee.
10. Obtain and retain the Sales and Use Tax Permit.
11. Record the assigned filing frequency.
12. Configure invoicing before the first taxable billing cycle.

For businesses using recurring invoices or stored payment credentials, tax configuration should remain separate from payment-data security. Understanding how tokenization and encryption protect card information differently can help reduce unnecessary exposure to card data, but neither technology determines whether a Connecticut service is taxable.

Filing Frequencies, Due Dates, and How to Show Tax on Invoices

Connecticut uses monthly, quarterly, and annual filing frequencies tied to sales-and-use-tax liability.

Under Conn. Gen. Stat. §12-414, taxpayers with less than $1,000 of total tax liability for the prior 12-month measurement period generally remit annually; those with at least $1,000 but less than $4,000 generally remit quarterly; and others generally remit monthly, subject to special DRS rules. Returns are due on or before the last day of the month following the filing period.

Step	Requirement	Deadline/Frequency	Source
Register	Before taxable sales where registration is required	Before selling	DRS
Permit fee	$100	At registration	DRS
File Form OS-114	Electronically through myconneCT	Monthly, quarterly, or annual	DRS/statute
Monthly return	Report preceding month	Last day of following month	§12-414
Quarterly return	Calendar quarters	Last day of following month	§12-414
Annual return	Prior calendar year	January 31	§12-414
Zero return	File even with no taxable activity	Assigned filing deadline	DRS

DRS says Form OS-114 must be filed even if no sales were made or no tax is due.

How should sales tax appear on a service invoice?

Connecticut guidance historically permits tax to be separately stated or, where legally permitted, included in the stated price with appropriate “tax included” disclosure. For service-business accounting, a separate tax line is usually easier to audit and reconcile.

Illustrative invoice:

Invoice Line	Amount
Advisory consulting	$2,000.00
Taxable computer-processing service	$4,000.00
Connecticut tax at 1% on computer-processing line	$40.00
Total invoice	$6,040.00

This example assumes the $2,000 consulting component has been reviewed and determined not to fit a taxable category. If it were taxable management consulting, its own 6.35% tax treatment would need to be added.

Card receipts and processor settlements

The tax should reconcile from the invoice to the payment and accounting records.

Suppose the customer pays a $6,040 invoice by card. The processor may deposit less than $6,040 because it deducts a processing fee. That net bank deposit does not change the taxable selling price.

The accounting chain should preserve:

gross service charge + sales tax collected = customer payment

and separately:

customer payment – processor fee = net bank settlement

Sales tax collected should not be booked as ordinary service revenue.

Because processor fees can reduce the amount deposited into the bank, reconciliation should start with the gross invoice rather than the net settlement. Invoice processing and transaction-matching automation can help connect customer payments with invoices, refunds, and deposits, while the Connecticut tax treatment remains tied to the underlying service rather than the payment record.

Refunds

A full refund of a taxable charge should normally reverse the associated sales tax in the accounting records as well, subject to the applicable Connecticut return and credit rules.

Partial refunds require more care. If a customer receives a refund only for a non-taxable component, the business should not automatically reverse tax that applied to a different line.

Test refund logic before launch, especially for SaaS and recurring billing systems that generate credits automatically.

B2B Resale and Exemption Documentation

A corporate customer is not automatically exempt from connecticut sales tax on services.

If the underlying service is taxable, the seller generally needs a valid exemption or resale basis to sell it without collecting tax.

Connecticut permits resale treatment for qualifying services in specified circumstances. DRS explains that a business may issue a Connecticut resale certificate when it purchases a taxable service for resale, including where the purchased service becomes an integral, inseparable component of a taxable service the purchaser subsequently resells.

Situation	Taxable at Sale?	Documentation Needed
Business buys taxable service for its own operations	Generally yes	No resale certificate
Business buys qualifying taxable service for resale	Potentially exempt at purchase	Proper Connecticut resale certificate
Government or statutory exempt organization	Depends on exemption	Correct DRS exemption certificate
Customer merely says “we are tax exempt”	Do not rely on statement alone	Obtain valid certificate
Out-of-state reseller	May qualify	Documentation meeting Connecticut rules

A resale certificate is not a substitute for a business card, purchase order, W-9, or customer email.

DRS says the certificate should be properly completed and retained by the seller. The resale certificate includes identifying information, descriptions of what the purchaser sells and buys, and Connecticut registration information where required.

Resale versus ordinary business use

The key distinction is resale, not B2B status.

A Hartford MSP that buys a cloud security service and consumes it to operate its own business is not buying for resale merely because it has business customers.

If that MSP purchases a taxable service that becomes an integral, inseparable part of another taxable service sold to its client, Connecticut’s service-resale rule may apply. The exact facts and certificate requirements should be reviewed.

Exemption certificates

Connecticut maintains separate sales-and-use-tax exemption rules and certificate requirements for qualifying transactions, so sellers should match the customer’s claimed exemption to the appropriate statutory basis rather than treating every certificate as interchangeable.

Do not assume every nonprofit purchase is exempt, every government-related project qualifies, or one certificate works for all transactions.

A useful certificate review checks:

• customer legal name;
• address;
• Connecticut registration number where required;
• certificate date;
• service or property purchased;
• claimed exemption;
• signature;
• consistency with the customer’s actual business.

What Happens if You Never Collected Connecticut Sales Tax?

If a business discovers that it should have charged connecticut sales tax on services but did not, the first task is to calculate the exposure rather than immediately changing old filings without a plan.

DRS states that a seller is responsible for collecting sales and use tax and is liable for payment even if the tax was not collected from customers.

A historical review usually follows this path:

taxable sales identified → Connecticut-sourced sales isolated → exemptions removed → tax due calculated → filed returns compared → interest/penalty exposure analyzed → remediation option selected

Hypothetical margin impact

Assume a firm had $100,000 of Connecticut-sourced taxable management-consulting revenue that should have been taxed at 6.35%.

Hypothetical tax before interest or penalties:

$100,000 × 6.35% = $6,350

If the invoices were fixed at $100,000 and the firm cannot legally or practically recover the tax from customers after the fact, the $6,350 may have to be funded from the seller’s own margin.

The same concept applies to a 1% computer/data-processing error, although the amount differs.

Connecticut DRS audit

A Connecticut DRS audit can examine the records needed to determine what was sold, where it was used, and whether the correct tax was charged.

That can include:

Record	What It Shows	Why DRS May Review It
Contracts/SOWs	Actual services promised	Determines classification
Invoices	Service descriptions and tax charged	Tests taxability and rate
Customer ledger	Sales by customer	Reconciles revenue
General ledger	Revenue categories	Identifies omitted sales
Bank statements	Cash receipts	Supports reconciliation
Processor statements	Gross card payments, refunds	Cross-checks payment activity
Returns	Reported taxable/nontaxable sales	Establishes filed position
Exemption certificates	Claimed tax-free sales	Supports exemption
CRM/service records	Customer location and use	May support sourcing

Merchant-processing reports can help reconcile sales, but they do not independently prove taxability. A card processor sees a payment amount; it does not determine whether the charge was taxable consulting, 1% computer processing, non-taxable accounting, or a resale transaction.

Audit lookback

The ordinary deficiency-assessment statute generally gives DRS three years after the applicable period or filed return, whichever is later, to issue an assessment.

The statute specifically excludes fraud, intent to evade, and failure to file a return from that ordinary three-year limitation. That is why an unregistered nonfiler should not assume only three years are at issue.

Penalties and interest

Connecticut law provides for interest at 1% per month or fraction of a month on deficiency assessments. Negligence or intentional disregard can trigger a 15% deficiency penalty or $50 minimum, while fraud or intent to evade can trigger a 25% penalty. A separate nonfiler assessment provision includes a 15% or $50 minimum penalty.

Penalty application depends on the particular procedural posture and facts. Businesses should not calculate every historical problem using one generic percentage.

Voluntary Disclosure, Amended Returns, and Historical Cleanup

A business that has historical Connecticut exposure should evaluate voluntary disclosure before simply registering late and filing old returns.

Connecticut’s Voluntary Disclosure Program is intended for taxpayers seeking to address previously unreported or underreported Connecticut tax obligations. 

DRS states that qualifying participants may receive a limited lookback period and penalty relief while paying the agreed tax and interest. Eligibility is fact-specific, and prior contact from DRS can affect whether the program is available.

Historical cleanup workflow

1. List every service sold historically.
2. Determine which services were taxable in each period.
3. Identify Connecticut-sourced sales.
4. Identify affected filing periods.
5. Calculate tax that should have been collected.
6. Remove supported exempt/resale sales.
7. Compare the result with returns already filed.
8. Determine whether the business is a filer, nonfiler, or underreporter.
9. Check whether DRS has already contacted the business.
10. Evaluate voluntary disclosure.
11. Evaluate amended returns where appropriate.
12. Register correctly for prospective periods.
13. Create service-level tax codes.
14. Correct billing/POS settings.
15. Document the remediation decision.

Amended returns

DRS currently allows previously filed returns to be amended through myconneCT. The portal provides a “View or Amend Return” process for filed periods.

An amended return may be appropriate where the business was already registered and filed but reported taxable sales incorrectly.

A nonfiler with multiple years of unregistered exposure is a different problem and should review the voluntary-disclosure process before assuming amended-return procedures are the right path.

Overcollection

Collecting tax on a non-taxable service is not a harmless error.

Amounts collected as sales tax should not simply be retained as ordinary revenue. The seller should determine how Connecticut’s refund, credit, and return-correction rules apply, including whether customers must be refunded before the seller seeks relief.

Correct the underlying tax code as well. Otherwise the same overcollection will repeat on the next invoice.

Common Misconceptions About Connecticut Service Tax

“Connecticut does not tax services.”

Incorrect. Connecticut taxes a long list of specifically enumerated services.

“Every service is taxed at 6.35%.”

Incorrect. Qualifying computer/data-processing services use the 1% special rate, while non-enumerated services may fall outside sales tax.

“All consulting is exempt.”

Incorrect. Business analysis, management, and management consulting are specifically listed as taxable services.

“All SaaS is taxed at 6.35%.”

Incorrect. Business-use electronically accessed canned software and qualifying computer/data-processing services are currently listed at 1%. The exact product still has to be classified.

“Every IT service gets 1%.”

Incorrect. Hardware repair, management consulting, or other taxable categories can carry different treatment.

“B2B sales are tax-free.”

Incorrect. A business customer can owe sales tax unless a valid resale or exemption rule applies.

“My processor handles the sales tax.”

Usually incorrect. The seller remains responsible for classifying the service, collecting tax when required, and reporting the transaction correctly. Processor charges are a separate payment-cost issue and should not be netted against tax liability.

Businesses that accept cards should also keep sales-tax decisions separate from Connecticut’s rules governing credit-card surcharges, cash discounts, and dual pricing. A lawful payment-pricing method does not change whether the underlying service is taxable.

“If I never collected it, only the customer owes it.”

Incorrect for the seller’s collection obligation. DRS says the seller is liable for tax it was required to collect even when collection did not occur.

“A resale customer does not need paperwork.”

Incorrect. DRS requires a properly completed resale or exemption certificate to support the tax-free sale.

Common Connecticut Service-Tax Mistakes

Mistake	Exposure	Better Approach
Using one generic “service” item	Wrong tax code applied broadly	Map tax codes by SKU/service
Treating all consulting as exempt	Missed taxable management consulting	Classify scope against §12-407
Taxing all IT at 1%	Under/overcollection	Separate computer processing, repair, consulting, hardware
Using one SaaS tax rule nationwide	State-specific errors	Apply Connecticut-specific classification
Using customer billing address only	Sourcing error	Review delivery/intended use
Failing to register	Permit and filing exposure	Complete Connecticut service business sales tax registration
Missing zero returns	Filing penalties/notices	Calendar every assigned return
Accepting “tax exempt” by email	Unsupported exemption	Obtain valid certificate
Treating every B2B sale as exempt	Undercollection	Confirm resale/statutory basis
Reconciling from net card deposits	Understated gross sales	Reconcile gross sale, tax, fee, settlement separately
Ignoring historical periods	Continuing exposure	Quantify and evaluate remediation

Real-World Connecticut Service Tax Examples

Example 1 — Hartford IT consultant

A Hartford IT firm charges $5,000 per month for remote monitoring, help desk, software maintenance, and quarterly executive technology advice.

The monitoring, help desk, and software-maintenance components may fit computer/data processing at 1%. The executive advisory component could require separate analysis, especially if it rises to taxable business-management consulting.

The firm should not label the whole invoice “IT consulting” and apply one assumed rate without documenting the components.

Example 2 — SaaS company

A SaaS provider sells access to a hosted business application to a Connecticut customer.

Current DRS guidance places electronically accessed canned software purchased by a business for business use at 1%. If the product instead includes distinct implementation, training, data services, hardware, or management consulting, those components should be reviewed separately.

Example 3 — CPA firm

A Hartford CPA firm bills $8,000 for audit and accounting services and $500 for access to a separate hosted reporting platform.

The accounting fee itself is generally outside the enumerated taxable-service list. The separately sold software or data-access component may fall under the 1% computer/data-processing or electronically accessed software rule.

The firm should document why the two components receive different tax treatment.

Example 4 — Marketing/technology agency

An agency bills for branding strategy, website development, website hosting, and monthly analytics reporting.

Current DRS guidance expressly lists website creation, development, hosting, and maintenance under computer/data-processing services. Advertising and public-relations services may also be taxable under their own category, while campaign or strategy services require exact-scope review.

A single “monthly marketing retainer” line can obscure several tax categories.

Example 5 — Remote vendor

A Massachusetts service company sells a taxable online service to Connecticut customers.

It must first determine whether those sales are Connecticut-sourced. It then tests Connecticut’s remote-seller rules. DRS currently requires an out-of-state seller to register when it has 200 or more Connecticut retail sales and at least $100,000 of gross Connecticut receipts during the relevant 12-month measurement period, unless another physical-presence rule already creates the obligation.

Example 6 — Reseller

A technology integrator buys a taxable service from a vendor and incorporates that service as an integral, inseparable component of a taxable service it resells to clients.

Connecticut allows service resale treatment in qualifying circumstances. The purchaser must provide proper resale documentation rather than simply telling the vendor it is buying “for a customer.”

Questions to Ask a CPA or Connecticut DRS

1. Is my exact service enumerated as taxable?
2. Which Connecticut rate applies?
3. Does the computer/data-processing treatment apply?
4. How should SaaS be classified?
5. Is separately stated consulting genuinely a separate service?
6. Where is the service delivered or intended for use?
7. Do my remote sales create Connecticut nexus?
8. Do I need a CT sales tax permit?
9. Which filing frequency will DRS assign?
10. Are my B2B customers taxable?
11. Which resale certificate applies?
12. How long should exemption documentation be retained?
13. What happens if prior tax was not collected?
14. Does voluntary disclosure make sense?
15. How should overcollection be corrected?

Connecticut Service Taxability and Invoice Setup Checklist

• List every service sold.
• Separate bundled service components.
• Verify the current taxable services Connecticut list.
• Identify regular-rate taxable services.
• Identify 1% computer and data processing tax CT services.
• Identify non-taxable professional services.
• Review SaaS treatment.
• Review managed IT treatment.
• Review software implementation and support.
• Check customer location and service sourcing.
• Confirm Connecticut nexus.
• Determine Connecticut service business sales tax registration requirements.
• Obtain a CT sales tax permit.
• Record the assigned filing frequency.
• Create invoice-level tax codes.
• Test a regular-rate service invoice.
• Test a computer/data-processing invoice.
• Test a non-taxable service invoice.
• Test a mixed invoice.
• Review B2B resale/exempt accounts.
• Obtain valid certificates.
• Test refunds and credits.
• Separate tax from processing fees.
• Reconcile tax collected monthly.
• Retain invoices and certificates.
• Review historical exposure.
• Evaluate voluntary disclosure or amended returns.
• Recheck taxability whenever services or products change.

Practical Connecticut Service-Tax Workflow

1. List every service sold. Use actual invoice items rather than department names.
2. Separate each billing component. Identify software, consulting, support, hardware, hosting, data work, training, and reimbursed expenses.
3. Pull current DRS guidance. Do not rely on an old tax matrix.
4. Determine whether each service is enumerated.
5. Determine whether computer/data-processing treatment applies.
6. Determine where the customer receives or uses the service.
7. Determine Connecticut nexus.
8. Identify B2B resale and exemption situations.
9. Collect valid certificates before suppressing tax.
10. Register when required.
11. Obtain the CT sales tax permit.
12. Record DRS filing frequency.
13. Create service-level invoice tax codes.
14. Configure billing, accounting, ecommerce, and POS systems.
15. Test a 6.35% taxable-service invoice.
16. Test a 1% computer/data-processing invoice.
17. Test a non-taxable professional-service invoice.
18. Test a mixed invoice.
19. Test an exempt/resale customer.
20. Test full and partial refunds.
21. Begin collecting from the required effective date.
22. Reconcile tax collected to invoices monthly.
23. File Form OS-114 on the assigned schedule.
24. Retain contracts, invoices, returns, certificates, and sourcing records.
25. Review historical periods separately.
26. Evaluate voluntary disclosure or amendments where appropriate.
27. Repeat the analysis whenever the product or service offering changes.

Frequently Asked Questions

Final Takeaway

Connecticut sales tax on services is a classification problem before it is an invoicing problem. Connecticut taxes specifically enumerated services rather than every form of professional labor, and the correct result can be 6.35%, the 1% computer/data-processing rate, or no sales tax at all depending on the service.

That makes component-level analysis especially important for SaaS companies, MSPs, software implementers, website developers, agencies, and consulting firms. A single contract can contain computer processing, taxable management consulting, non-taxable professional work, software, and hardware.

B2B status does not automatically remove the tax. A taxable service needs a legitimate resale or exemption basis, supported by appropriate documentation, before the seller suppresses tax.

Once the classification is settled, the operational sequence is straightforward: confirm Connecticut sourcing and nexus, complete Connecticut service business sales tax registration, obtain the CT sales tax permit, configure service-level tax codes, show tax clearly on invoices, reconcile gross sales separately from processor fees, file on the assigned schedule, and retain exemption records.

Historical missed collections should be treated as a separate remediation project. Quantify the exposure first, then evaluate amended returns, voluntary disclosure, and prospective corrections with appropriate professional guidance.