Functional Finance

Functional Finance

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Partner program · Payment rails

You move the payments. We keep every one accounted for.

We build and maintain the connection to your API, then route our clients' card and ACH payments through your rail. You authorize, settle and pay out; Functional Finance turns every result into paid invoices, applied cash and a balanced ledger.

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Why partner with us

  • Insurance payment volume

    Card and ACH payments from MGAs, carriers, agencies and premium finance companies, routed to your rail.

  • We build the connection

    Functional Finance builds and maintains the connection to your API. You provide a sandbox, documentation and a technical contact.

  • Beside other rails

    A client can run your rail alone or in priority order with others, and its billing and ledger stay untouched.

Who this is for

Card processors, ACH providers and acquirers that authorize, settle and pay out for merchants.

  • Card processors and acquirers

  • ACH providers that originate debits and report returns

  • Providers that board merchants and pay out settled funds

How it works

One payment, end to end: who sends what, to whom.

  1. Step 1: Payer to Functional Finance.

    Pays an invoice

    Card or bank details go into a vault's hosted field, never to Functional Finance.

  2. Step 2: Functional Finance to Your rail.

    Payment request

    Names the card or bank account by your own id, never the number.

  3. Step 3: Your rail to Functional Finance.

    Result

    Authorized, captured or declined, with the real reason.

  4. Step 4: Your rail to Client's bank.

    Funding batch

    Net settled funds, every fee itemized.

  5. Step 5: Your rail to Functional Finance.

    Settlement report

    Transactions, payouts and fees, read on a schedule.

  6. Step 6: Functional Finance.

    Reconcile

    Batch matched, cash applied, ledger posted.

Build it with AI

Your engineers start from a ready-made prompt

Once your developer access is approved, each program's interface page gives you a ready-made AI prompt: the contract, every key flow and the events, grounded in our API reference, OpenAPI spec and llms.txt.

Paste it into Claude, Cursor, GitHub Copilot, Codex, Windsurf, Replit or Lovable.

See the full interface

Who does what

Payments
YouAuthorize, capture, clear, settle.
Functional FinanceCreates each payment from an invoice and picks the rail.
Merchants
YouBoard merchants (KYB) and hold their identity.
Functional FinanceSends boarding details; keeps settlement accounts verified.
Payouts
YouPay out funding batches with fees itemized.
Functional FinanceReconciles each batch; records every fee.
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Disputes and returns
YouRun chargebacks and ACH returns with the networks.
Functional FinanceKeeps the record, responds through you, reverses cash explicitly.
The books
YouReport with stable identifiers.
Functional FinanceOwns invoices, cash application, ledger and payables.

The full interface, for approved developers

Contracts, events, error handling and testing flows are in the developer portal, open to anyone whose developer access is approved.

Open the interface detail

How to become a partner

  1. Agree

    1. Step 1: Introduction

      Your rails, markets and merchants.

    2. Step 2: Due diligence

      PCI DSS attestation, SOC 2 report, licensing.

    3. Step 3: Agreement

      Fees, payout timing, dispute handling.

  2. Build

    1. Step 4: Sandbox integration

      Functional Finance builds the connection to your API.

    2. Step 5: End-to-end testing

      Boarding, charges, refunds, settlement, returns, disputes.

  3. Run

    1. Step 6: Go live

      Clients routed to your rail, alone or in priority order.

    2. Step 7: Operate

      Transactions, payouts and disputes kept in sync.

Compliance

  • Card and bank numbers reach you through the vault proxy, never through Functional Finance.

  • You keep your own PCI DSS compliance and payment licensing.

  • Every transaction, batch and fee is an explicit, auditable record.

Questions partners ask

Not necessarily. A client can use more than one rail in priority order, and adding or swapping a rail leaves its billing and ledger untouched.

No. Card and bank numbers are captured in a vault's hosted fields and forwarded to your rail through the vault's proxy.

It reads them from your API on a schedule, and each run continues from where the last one stopped.

Talk to us about becoming a payment partner

Tell us about your rails and the merchants you serve, and we'll be in touch about fit and next steps.