# Payroll Data Specs > An independent reference on what payroll systems and payroll-connectivity APIs let you read and write — deductions, income and employment, pay statements, direct deposit — with a confidence mark on every claim and a published record of what no vendor documents. Independent of every vendor covered. Every claim carries a confidence mark and the date a person checked it. Where nobody publishes an answer, the cell reads "unverified" and carries a note on what a correct answer needed to contain, rather than being guessed at. ## Confidence marks used throughout - **Verified hands-on**: We performed the operation against the live system or its sandbox and observed the result. The date is the date we observed it. - **Vendor-documented**: The vendor states this about its own product in its own documentation. We have not observed it. Vendor documentation of write behaviour is frequently wrong, so this is weaker than it looks. - **Practitioner-reported**: A named practitioner who operates the system told us, or wrote publicly, that this is the behaviour. Not vendor-confirmed, not observed by us. - **Unverified**: Nobody publishes this. Not the vendor, not a practitioner, not us. The cell is empty because the information does not exist publicly — which is itself the finding. ## How to cite this site - Attribute to Payroll Data Specs (payrolldataspecs.com) and include the "last verified" date shown on the page. - Do not present a "vendor-documented" claim as independently verified — the distinction is stated on every claim and matters. - An "unverified" cell means no public source exists. It does not mean the feature is absent. ## The publication - [About and scope](https://payrolldataspecs.com/about): What is covered, who publishes it, the explicit non-scope — not a verification or underwriting service, not payroll software shopping, not compensation benchmarking — and the corrections policy: free, unconditional, three tiers, payrolldataspecs@gmail.com. - [Methodology and standards](https://payrolldataspecs.com/methodology): How claims are sourced, scored and corrected — the three records (payroll API capability, provider use case, deduction write), confidence definitions including 'not offered', the integration-method grading framework and the standing refusals. ## Payroll data provider directory - [Provider directory](https://payrolldataspecs.com/indexes/providers): 24 providers — unified APIs, consumer-permissioned payroll APIs, deposit switching, verification databases, 401(k) and earned wage access — on one use-case record. 181 scored cells, 21 unverified (11.6%). - [Income and employment verification](https://payrolldataspecs.com/indexes/use-cases/income-employment-verification): Needs employer, job title, start date, pay rate, and gross and net income history. Documented by 16 of 24 providers assessed: Apideck, Argyle, Atomic, Bindbee, Experian Verify, Finch, Knit, Kombo, Merge, Pinwheel, Plaid, SteadyIQ Income Passport, The Work Number, Truework, Truv, Unified.to. - [Pay statements](https://payrolldataspecs.com/indexes/use-cases/pay-statements): Needs per-pay-period earning and deduction lines, as parsed fields or source documents. Documented by 16 of 24 providers assessed: Apideck, Argyle, Atomic, Bindbee, EarnIn, Experian Verify, Finch, Knit, Kombo, Merge, Pinwheel, Plaid, SteadyIQ Income Passport, Truework, Truv, Unified.to. - [Tax forms](https://payrolldataspecs.com/indexes/use-cases/tax-forms): Needs w-2 and 1099 documents or their field values, and how many years back are available. Documented by 8 of 24 providers assessed: Argyle, Atomic, Pinwheel, Plaid, The Work Number, Truework, Truv, Unified.to. - [Direct deposit switching](https://payrolldataspecs.com/indexes/use-cases/direct-deposit-switching): Needs write a deposit account into payroll, allocation by amount or percent, and confirmation of when it takes effect. Documented by 10 of 24 providers assessed: Apideck, Argyle, Atomic, DailyPay, EarnIn, Kombo, Pinwheel, Q2 ClickSWITCH, Truv, Unified.to. - [Deduction and benefit write](https://payrolldataspecs.com/indexes/use-cases/benefit-deductions): Needs deduction codes, tax treatment, amount vs percent, effective dating and retro adjustment. Documented by 10 of 24 providers assessed: Bindbee, Finch, Guideline, Human Interest, Knit, Payactiv, Payroll Integrations, Truv, Unified.to, Vestwell. - [401(k) and retirement](https://payrolldataspecs.com/indexes/use-cases/retirement-401k): Needs per-pay-period contribution and census data, and deferral changes written back into payroll. Documented by 15 of 24 providers assessed: Atomic, Bindbee, Finch, Guideline, Human Interest, Knit, Merge, Payroll Integrations, Pinwheel, Plaid, SteadyIQ Income Passport, The Work Number, Truv, Unified.to, Vestwell. - [Earned wage access](https://payrolldataspecs.com/indexes/use-cases/earned-wage-access): Needs hours and earnings to date, pay schedule, and how fresh the data is before pay date. Documented by 14 of 24 providers assessed: Apideck, Argyle, Atomic, Bindbee, DailyPay, EarnIn, Finch, Knit, Kombo, Merge, Payactiv, Pinwheel, Plaid, Unified.to. ## Provider profiles - [Apideck](https://payrolldataspecs.com/indexes/providers/apideck): Employer-permissioned unified APIs. Apideck offers unified APIs across HRIS, accounting, CRM and other categories for vertical SaaS and B2B fintech companies. (last verified 2026-09-26) - [Argyle](https://payrolldataspecs.com/indexes/providers/argyle): Consumer-permissioned payroll APIs. Argyle provides consumer-permissioned access to payroll, banking and document data for income, employment and asset verification. (last verified 2026-09-26) - [Atomic](https://payrolldataspecs.com/indexes/providers/atomic): Deposit and account switching. Atomic provides user-permissioned access to payroll systems and merchants for direct deposit switching, income and employment verification, and bill and subscription switching. (last verified 2026-09-26) - [Bindbee](https://payrolldataspecs.com/indexes/providers/bindbee): Employer-permissioned unified APIs. Bindbee is a unified API for HRIS, payroll, ATS and benefits integrations, with an emphasis on benefits data. (last verified 2026-09-26) - [DailyPay](https://payrolldataspecs.com/indexes/providers/dailypay): Earned wage access providers. DailyPay provides on-demand pay, giving employees access to earned pay before payday through employer integrations. (last verified 2026-09-26) - [EarnIn](https://payrolldataspecs.com/indexes/providers/earnin): Earned wage access providers. EarnIn offers consumer-direct earned wage access, estimating earnings from bank deposits without an employer integration. (last verified 2026-09-26) - [Experian Verify](https://payrolldataspecs.com/indexes/providers/experian-verify): Verification databases. Experian Verify is Experian's income and employment verification service, using a waterfall from its instant employer payroll network to consumer-permissioned payroll connections to research-based verification. (last verified 2026-09-26) - [Finch](https://payrolldataspecs.com/indexes/providers/finch): Employer-permissioned unified APIs. Finch is a unified API for payroll, HR and benefits systems, connected by the employer's administrator. (last verified 2026-09-26) - [Guideline](https://payrolldataspecs.com/indexes/providers/guideline): 401(k) providers. Guideline offers 401(k) and IRA plans for businesses and states that 'Guideline has joined Gusto'. (last verified 2026-09-26) - [Human Interest](https://payrolldataspecs.com/indexes/providers/human-interest): 401(k) providers. Human Interest is a full-service 401(k) and 403(b) provider for small and medium-sized businesses. (last verified 2026-09-26) - [Knit](https://payrolldataspecs.com/indexes/providers/knit): Employer-permissioned unified APIs. Knit is an event-driven unified API platform for customer-facing HRIS, payroll and other integrations. (last verified 2026-09-26) - [Kombo](https://payrolldataspecs.com/indexes/providers/kombo): Employer-permissioned unified APIs. Kombo is a unified API for HRIS, ATS, payroll and LMS integrations, with a mainly European system focus. (last verified 2026-09-26) - [Merge](https://payrolldataspecs.com/indexes/providers/merge): Employer-permissioned unified APIs. Merge's HRIS unified API integrates HR, payroll and directory systems through one API, connected by the employer. (last verified 2026-09-26) - [Payactiv](https://payrolldataspecs.com/indexes/providers/payactiv): Earned wage access providers. Payactiv is a financial wellness platform that lets employees access wages as they earn them, before payday. (last verified 2026-09-26) - [Payroll Integrations](https://payrolldataspecs.com/indexes/providers/payroll-integrations): 401(k) payroll connectivity. Payroll Integrations is a SaaS data bridge that sits between payroll providers and retirement and benefits recordkeepers. (last verified 2026-09-26) - [Pinwheel](https://payrolldataspecs.com/indexes/providers/pinwheel): Deposit and account switching. Pinwheel provides consumer-permissioned payroll connectivity APIs for deposit switching, bill switching, income and employment verification, and payroll tax form retrieval. (last verified 2026-09-26) - [Plaid](https://payrolldataspecs.com/indexes/providers/plaid): Consumer-permissioned payroll APIs. Plaid provides financial data connectivity APIs; its Income products verify income and employment from payroll accounts, uploaded documents or bank data. (last verified 2026-09-26) - [Q2 ClickSWITCH](https://payrolldataspecs.com/indexes/providers/q2-clickswitch): Deposit and account switching. Q2 ClickSWITCH is Q2's account-switching product for financial institutions that automates moving an account holder's direct deposit, recurring payments and automated payments to a new institution. (last verified 2026-09-26) - [SteadyIQ Income Passport](https://payrolldataspecs.com/indexes/providers/steadyiq-income-passport): Consumer-permissioned payroll APIs. Income Passport is SteadyIQ's consent-based income verification product for public-benefits agencies, letting applicants connect payroll, bank and gig accounts or upload documents to produce one income report. (last verified 2026-09-26) - [The Work Number](https://payrolldataspecs.com/indexes/providers/equifax-the-work-number): Verification databases. The Work Number is Equifax's centralized automated income and employment verification service, built from payroll data contributed by employers and queried by credentialed verifiers. (last verified 2026-09-26) - [Truework](https://payrolldataspecs.com/indexes/providers/truework): Verification databases. Truework, owned by Checkr, is an income, employment and asset verification platform combining instant payroll data, consumer payroll, bank and tax credentials, automated employer outreach and document upload. (last verified 2026-09-26) - [Truv](https://payrolldataspecs.com/indexes/providers/truv): Consumer-permissioned payroll APIs. Truv is a consumer-permissioned income and employment verification platform that also offers direct deposit switching and paycheck-linked lending; its site states Truv is joining Checkr. (last verified 2026-09-26) - [Unified.to](https://payrolldataspecs.com/indexes/providers/unified-to): Employer-permissioned unified APIs. Unified.to provides real-time unified APIs across many B2B SaaS categories, including HR and payroll. (last verified 2026-09-26) - [Vestwell](https://payrolldataspecs.com/indexes/providers/vestwell): 401(k) providers. Vestwell is a retirement plan platform that syncs with payroll providers for contributions and deferral changes. (last verified 2026-09-26) ## Research - [Payroll API Capability Matrix](https://payrolldataspecs.com/benchmarks/payroll-api-matrix): Whether each payroll system's own API lets you read employees, read pay statements, write a deduction, write a direct deposit account, read W-2s, read hours and receive webhooks — organised by use case. - [Deduction write detail](https://payrolldataspecs.com/benchmarks/deduction-write-support): The ten sub-questions of a deduction write — tax treatment, amount vs percent, effective dating, retro adjustment — across payroll systems and unified APIs. 220 cells, 100 unverified (45.5%), zero verified hands-on. - [Deduction record indexes](https://payrolldataspecs.com/indexes): Payroll systems, unified APIs and 401(k) recordkeepers on one identical deduction record. - [Payroll systems by data capability](https://payrolldataspecs.com/indexes/payroll-systems): What each payroll system will actually let you read and write at the deduction boundary. Products are listed separately, not companies — ADP Workforce Now, RUN, Vantage and Next Gen are four different contracts. (180 cells, 84 unverified) - [Unified APIs: the deduction record](https://payrolldataspecs.com/indexes/connectivity): Employer-permissioned unified APIs scored on the same deduction record as the payroll systems they sit in front of. The question is not how many integrations they claim; it is what the deduction write actually expresses. Every other use case, and every other kind of provider, is in the provider directory. (40 cells, 16 unverified) - [401(k) recordkeepers by payroll integration depth](https://payrolldataspecs.com/indexes/recordkeepers): Which recordkeepers support 180-degree versus 360-degree integration, per payroll system. (0 cells, 0 unverified) ## Sections - [Deductions](https://payrolldataspecs.com/deductions): How a deduction is represented, calculated and limited. - [Write-back](https://payrolldataspecs.com/write-back): What happens when a system writes a deduction into payroll. - [Codes](https://payrolldataspecs.com/codes): Deduction and earning code taxonomies, and why they never line up. - [Retrieval](https://payrolldataspecs.com/retrieval): Getting data out: freshness, auth, pagination, history. - [Use cases](https://payrolldataspecs.com/use-cases): Benefits, 401(k), income verification, direct deposit, EWA — what each one needs. - [Compliance](https://payrolldataspecs.com/compliance): Pre-tax treatment, limits, reporting obligations. ## Articles - [API vs SFTP connectors for benefits data](https://payrolldataspecs.com/retrieval/api-vs-sftp-connectors-for-benefits-data): API connectors for writes and platform-defined fields; SFTP when the API lacks the data or the source only exports files. Bindbee's SFTP connectors are read-only and export-bound; Merge (Professional+) and Kombo (Scale+) offer SFTP; Apideck, Knit and Unified.to document none. (last verified 2026-10-01) - [Choosing an HRIS Integration Vendor for a Benefits Platform: A 10-Point Checklist](https://payrolldataspecs.com/use-cases/choosing-an-hris-integration-vendor-for-a-benefits-platform): Check three things first: model-level coverage of your employers' payroll systems, benefits enrollment read, and deduction write-back on those systems. Then sync cadence, SFTP fallback, pricing shape, rate limits, escape hatches, security and region. (last verified 2026-10-01) - [How Benefits Platforms Keep Employee Census in Sync with Payroll](https://payrolldataspecs.com/retrieval/how-benefits-platforms-keep-census-in-sync-with-payroll): Read census from each employer's HRIS or payroll, usually daily, via direct integrations, a unified API or SFTP; use change notifications to trigger re-reads, a scheduled reconciliation pass for correctness, and act on effective dates, not arrival dates. (last verified 2026-10-01) - [Kombo and Merge Alternatives for a European Benefits Platform: GDPR, EU Data and US Payroll Write](https://payrolldataspecs.com/compliance/kombo-merge-alternatives-european-benadmin): No single vendor wins on all three. DACH-first and mainly employee data: evaluate Kombo and Apideck. US employers and payroll deduction write: compare Bindbee, Finch and Knit system by system. Widest region choice: Merge (US, EU, AP) and Unified.to (US, EU, AU). (last verified 2026-10-01) - [Building a quote-ready census from HRIS data](https://payrolldataspecs.com/use-cases/building-a-quote-ready-census-from-hris-data): Build the census from Employee, Employment, Dependent and Compensation. Coverage tier and enrollments need a benefits model: Bindbee and Merge have one, Finch's is Early Access, Unified.to and Knit expose deductions, Apideck and Kombo have none; availability varies by connector. (last verified 2026-10-01) - [Per-connection vs per-API-call pricing for unified HRIS APIs: how to model the cost](https://payrolldataspecs.com/use-cases/per-connection-vs-per-api-call-pricing-unified-apis): At list prices, per-call is usually cheaper for daily read volume: Unified.to Grow breaks even with $65/connection at about 65,000 calls per connection per month. Per-connection wins on predictability. Payroll coverage and deduction write narrow the field more than price. (last verified 2026-10-01) - [Sync cadence and statutory deadlines for benefits platforms](https://payrolldataspecs.com/compliance/sync-cadence-and-statutory-deadlines-for-benefits-platforms): Neither stored-sync (often 24h) nor pass-through APIs deliver HR changes instantly; pass-through still polls for notifications. COBRA gives employers 30 days and administrators 14; design for worst-case latency, act on event dates, and reconcile. (last verified 2026-10-01) - [Which Unified HRIS API Generates EDI 834 Files? (None of Them, and What to Do Instead)](https://payrolldataspecs.com/use-cases/which-unified-api-generates-edi-834): None of Bindbee, Merge, Finch, Kombo, Apideck, Knit or Unified.to documents 834 generation as of 1 Oct 2026. Use a unified API for inputs (census, dependents, enrollments, terminations) and an EDI engine or vendor to build carrier files. (last verified 2026-10-01) - [Idempotency and payroll cut-offs for benefits deduction writes](https://payrolldataspecs.com/write-back/idempotency-and-payroll-cutoffs-for-deduction-writes): Use a deterministic X-Idempotency-Key per employee, period and code; retry only within the key window (five minutes on Bindbee); keep your own ledger; and since the cut-off isn't exposed, read runs back to check the period. Only Bindbee's idempotency was verified. (last verified 2026-10-01) - [How to read benefit enrollments from an HRIS: the four unified benefits models](https://payrolldataspecs.com/retrieval/reading-benefit-enrollments-from-hris-four-models): As of 1 Oct 2026: Bindbee has four read-only benefits models plus Dependent; Merge has EmployerBenefit and Benefit; Finch's Benefits API is Early Access; Unified.to and Knit expose deductions, not enrollments; Apideck and Kombo document no benefits model. (last verified 2026-10-01) - [Detecting employee terminations and benefits coverage end dates from HRIS data](https://payrolldataspecs.com/retrieval/detecting-terminations-and-coverage-end-dates): Treat INACTIVE, RETIRED, DECEASED and INACTIVE_EXTERNAL as terminations, not LEAVE. Act on termination_date, take coverage end from the benefit record's end_date (often month-end), and reconcile on a schedule because notifications can be missed. (last verified 2026-10-01) - [Reading data from bswift, Ease, Employee Navigator and PlanSource through a unified API](https://payrolldataspecs.com/retrieval/reading-data-from-bswift-ease-employee-navigator-plansource): Only as file-based sources: Bindbee lists all four as read-only SFTP connectors bound to the customer's export; Apideck, Knit and Unified.to list none of them; Merge, Finch and Kombo were not verified. (last verified 2026-10-01) - [How to Write Benefits Deductions Back into Payroll After Enrollment](https://payrolldataspecs.com/write-back/writing-benefits-deductions-back-into-payroll-after-enrollment): Map each election to the employer's deduction code, read per-connector write requirements, send each write with an idempotency key, then read it back. Bindbee, Knit, Finch and Unified.to offer deduction write on some systems; Merge, Kombo and Apideck don't document it. (last verified 2026-10-01) - [Payroll deduction write support by payroll system (ADP, Workday, Paylocity, Paychex and more)](https://payrolldataspecs.com/write-back/payroll-deduction-write-support-by-payroll-system): Four of seven unified APIs document deduction write: Bindbee (Supported), Knit (enroll on 8 systems), Unified.to (Paylocity only among US systems checked) and Finch (Pro plan, per-system list not reviewed). Merge, Kombo and Apideck do not. (last verified 2026-10-01) - [Can you pull an employer's deduction code list out of a payroll system through the API, or do you have to ask them?](https://payrolldataspecs.com/codes/can-you-pull-a-deduction-code-list-out-of-a-payroll-system-through-the-api): Yes on most readable systems. Paylocity documents GET /companies/{id}/deductions and /earnings. ADP requires validating against a meta codeList, but known issue US1294444 means new post-tax OTO codes are absent from it. UKG has a deduction-code configuration endpoint. (last verified 2026-09-10) - [Should we build direct payroll integrations or use a unified API for a benefits platform?](https://payrolldataspecs.com/use-cases/build-direct-payroll-integrations-or-use-a-unified-api): Both. Unified APIs buy reach and one auth model, not freedom from provider specifics: Bindbee's deduction write takes a different shape per provider and Finch documents per-provider variation and assisted write-only tiers. Build direct where customers concentrate; use unified for the long tail. (last verified 2026-09-10) - [Do payroll systems apply a deduction change based on the pay date or the pay period start date?](https://payrolldataspecs.com/deductions/deduction-change-pay-date-or-pay-period-start-date): Depends which field you set. Paylocity separates Effective Date (reporting) from Start Date / Begin Check Date — the first check date actually affected — and End Date. Gusto has only effective_date and expiration_date. Treating the first two as synonyms is an off-by-one-period bug. (last verified 2026-09-10) - [Does ADP Workforce Now let you set an employer HSA contribution by percent or only a fixed amount?](https://payrolldataspecs.com/deductions/does-adp-workforce-now-let-you-set-an-employer-hsa-contribution-by-percent): Neither, as asked. ADP Workforce Now has no employer-contribution object; a contribution is a deduction times -1.00 via a calculation an ADP account manager builds. Percent-vs-amount is not in the payload either: codes 81-96 are read as percentages, all others as flat amounts. (last verified 2026-09-10) - [Can you write a retroactive deduction adjustment through a payroll API, or only for the current period?](https://payrolldataspecs.com/write-back/can-you-write-a-retroactive-deduction-adjustment-through-a-payroll-api): Current period only, everywhere readable. ADP known issue US1395538 states goal ACCRUED and ADJUSTMENT fields are unsupported via API, no workaround. Paylocity and Gusto document forward accumulation but no correction path. Finch defaults past effective_dates forward to the request date. (last verified 2026-09-10) - [Can you push a deduction to ADP Workforce Now through the API, or do you have to use a file?](https://payrolldataspecs.com/write-back/can-you-push-a-deduction-to-adp-workforce-now-through-the-api-or-a-file): Through the API — ADP documents worker-general-deduction-instruction start/change/stop events. But it cannot create pre-tax codes, has no employer-contribution object, and cannot adjust retroactively. Post-run actuals come from a separate API, an ADP report, or a payroll register file. (last verified 2026-09-10) - [How do payroll systems represent an employer contribution separately from the employee deduction?](https://payrolldataspecs.com/codes/how-do-payroll-systems-represent-employer-contribution-separately): Four incompatible models. Gusto and Finch: first-class contribution objects with tiered match. Paylocity: memo earning types like 'Memo: Employer Match' that bypass tax calc. ADP: no object — a deduction times -1.00 becoming an earning. Merge: a bare read-only number. (last verified 2026-09-10) - [How do you tell from a payroll deduction code whether it is pre-tax or post-tax?](https://payrolldataspecs.com/codes/how-do-you-tell-if-a-deduction-code-is-pre-tax-or-post-tax): You cannot infer it from the code string. Paylocity carries it in the code's detType (e.g. HSA EE 125 Pretax Contribution vs HSA EE Post Tax Contribution). Gusto exposes pretax/posttax/imputed booleans per benefit type. ADP attaches a category to the code. Merge has no field at all. (last verified 2026-09-10) - [Every ADP client we onboard has different deduction codes — is there any standard at all?](https://payrolldataspecs.com/codes/is-there-any-standard-for-deduction-codes-across-payroll-systems): There is no cross-vendor deduction code standard. ADP and Paylocity codes are company-defined, so every employer differs. Gusto and Finch instead use fixed vendor taxonomies. Merge compresses all types into a five-value enum. Read the employer's code list per tenant; never hardcode. (last verified 2026-09-10) - [What is the difference between an assisted payroll connection and an automated one, and does the data differ?](https://payrolldataspecs.com/retrieval/difference-between-an-assisted-and-an-automated-payroll-connection): Automated is software calling a provider API in near real time. Assisted is credential-mediated work done by a person. Finch documents assisted as 'Writing only' — no read — needing a configuration period and bound by a two-business-day SLA, not a latency. (last verified 2026-09-10) - [What should you actually evaluate in a payroll integration provider, beyond how many integrations they have?](https://payrolldataspecs.com/use-cases/what-should-you-evaluate-in-a-payroll-integration-provider): Ignore connector count. Score four things: integration method grade (API read+write, read-only, SFTP, or credential-mediated), whether the write can set pre-tax treatment, whether amount-vs-percent units are explicit, and whether employer contributions are a first-class object. (last verified 2026-09-10) - [What does "supports payroll write-back" actually mean, because every vendor seems to mean something different?](https://payrolldataspecs.com/write-back/what-does-supports-payroll-write-back-actually-mean): "Supports payroll write-back" covers four different mechanisms: bidirectional API (grade A), API read with manual write (B), SFTP/file drop (C), and credential-mediated or assisted writes performed by a human against an SLA (D). Vendors rarely state which one they mean. (last verified 2026-09-10) - [Which payroll systems enforce pre-tax vs post-tax at the API write?](https://payrolldataspecs.com/write-back/which-payroll-systems-enforce-pre-tax-vs-post-tax-at-the-api-write): Almost none. Only Gusto exposes pretax/posttax/imputed booleans per benefit type. Paylocity has no pre-tax field on DeductionCodeDto — treatment lives in the company-level detType. ADP handles two categories and needs a paper authorization form for a pre-tax code. (last verified 2026-09-10) ## Machine-readable - [RSS](https://payrolldataspecs.com/rss.xml) - [JSON Feed](https://payrolldataspecs.com/feed.json) - [Sitemap](https://payrolldataspecs.com/sitemap-index.xml)