Finix
Connect your merchants' Finix accounts to process card and ACH transactions through Preczn.
Connect your merchants' Finix accounts to process card and ACH transactions through Preczn.
Finix is a platform connection: your platform holds one set of Finix API credentials, and each merchant carries only their Finix merchant ID. Preczn authenticates every request with the platform credentials and names the individual merchant on the transaction.
Supported Capabilities
| Capability | Status | Notes |
|---|---|---|
| Credit Card Transactions | Supported | Full lifecycle — sale, auth, capture, void, refund, and verify |
| ACH (Bank Account) Transactions | Supported | Personal and business checking and savings |
| AVS and CVV Results | Supported | Returned on sale, auth, verify, and capture |
| Apple Pay / Google Pay | Not supported | Wallet transactions cannot be routed to Finix |
| Merchant Onboarding | Not supported | Merchants are boarded with Finix directly, then linked |
| Level II and Level III Data | Not supported | Enhanced data is stored on the Preczn transaction but not sent |
| Immediate settlement | Partial | Captures always land Pending — see Settlement Timing |
Supported Transaction Types
| Type | Description |
|---|---|
| Sale | Authorize and capture in a single request |
| Auth | Authorize only (hold funds without capturing) |
| Capture | Capture a previous authorization, in full or in part |
| Void | Cancel an authorization |
| Refund | Return funds from a completed transaction, in full or in part |
| Verify | Validate a card without charging it (see Verify) |
Adding Platform Credentials
Finix issues one API user to your platform. Both values are stored on the platform's Finix connection and are used for every merchant.
| Credential | API field | Description |
|---|---|---|
| Username | key | The Finix API username |
| Password | secret | The password paired with that username |
Preczn sends them as HTTP Basic authentication on every Finix request. Add them to the platform's Finix connection — see Connection Configuration.
Test and Live are configured separately, and Preczn selects the matching Finix environment from the mode a transaction runs in.
Adding Merchant Credentials
Each merchant needs one value: the merchant's ID in your Finix account.
| Credential | API field | Description |
|---|---|---|
| Merchant ID | mid | Identifies the merchant's Finix account on every request |
Enter it on the merchant's Finix connection in the Dashboard, or send it as mid to the connection update endpoint — see Linking Existing Credentials. Preczn verifies the merchant ID with Finix before saving it.
The identity is resolved for youFinix identifies the party behind a merchant with a separate identity value. Preczn reads it from Finix when it verifies the merchant ID and stores it on the connection automatically, so there is no second value to look up or enter.
Processing Transactions
Route transactions to Finix the same way as any other connection — through a plan or a direct connection reference on the transaction. The sections below cover the behavior specific to Finix.
Settlement Timing
Finix does not decide every transaction on the API response. Plan for two outcomes:
| Transaction type | What to expect |
|---|---|
| Sale, Auth, Verify | Usually A (Approved) or D (Declined) on the response, but P (Pending) is possible |
| Capture | Always P (Pending) — never Approved on the response |
| Void, Refund | Decided on the response |
A Pending transaction is finalized later by Finix. Preczn listens for that and updates the transaction on its own, so there is nothing to poll — subscribe to a webhook if your system needs to react when the final status lands.
The practical consequence: do not treat a capture's Pending status as a failure, and do not release goods on a Pending sale until the final status arrives.
ACH Transactions
Finix accepts bank-account payments alongside cards, for personal and business checking and savings accounts. See ACH (Direct Debit) for how to submit one.
Verify and Card Checks
A Verify on a Finix connection runs as a zero-dollar authorization, so it validates the card without moving money and without a capture to reverse.
Captures and Refunds
Captures and refunds may be for the full amount or a partial amount. A partial capture sends the requested amount; a full capture sends the amount of the original authorization.
AVS and CVV Results
Finix returns AVS and CVV results on sale, auth, verify, and capture. Send the billing street address and postal code to get a meaningful AVS result, and the CVV to get a card-code result. Finix distinguishes a full address match from a postal-code-only or street-only match, so a partial result is possible.
Data Not Sent to Finix
Finix's API has no equivalent for the following. Preczn accepts them and uses them elsewhere, but they never reach Finix:
- Metadata
- Level II and Level III data — tax, freight, and line-item detail
- The shipping address
Nothing sent to Finix is shortened or reformatted, so values arrive as submitted.
On a card transaction Preczn forwards the cardholder name, the billing address when supplied, and the dynamic statement descriptor. On a business checking or savings payment, the account holder name is the business name from the transaction rather than the individual's name.
Declines and Errors
A transaction Finix or the issuer rejects is D (Declined), with Finix's own reason on processorMessage and its trace ID on processorCode. A request Finix could not process at all — a connectivity problem or a malformed request — is E (Error). The distinction matters for retry logic: an Error is worth retrying, a Decline is not.
Testing in the Sandbox
- Configure the platform's Finix connection in Test Mode with your Finix sandbox username and password.
- Add each merchant's sandbox Finix merchant ID to their connection.
- Send transactions using the standard Preczn test cards.
To exercise declines and specific failure codes against Finix, ask Finix for the sandbox values that trigger them.
FAQ
Where do I find the merchant's Finix Merchant ID?
In your Finix dashboard, on the merchant's record. It is the identifier Finix assigns when the merchant is boarded to your Finix account. Preczn verifies it against Finix when you save, so a wrong value is caught at configuration time.
Do I need to enter a secret for each merchant?
No. Finix's per-merchant identity is read from Finix during verification and stored on the connection for you. The only value you supply is the Merchant ID.
Can I board new merchants to Finix through Preczn?
No. Preczn connects merchants who already exist in your Finix account; it does not submit applications to Finix. Board the merchant with Finix, then add their Merchant ID to the Preczn connection.
Can I send Apple Pay or Google Pay transactions?
No. Wallet transactions cannot be routed to Finix. Route wallet volume to a connection that supports it — see Apple Pay on the Web and Google Pay for Web.
Why is my capture Pending instead of Approved?
That is expected. Finix accepts a capture and settles it asynchronously, so every capture starts as P (Pending) and reaches its final status when Finix reports the outcome. Preczn updates the transaction automatically — subscribe to a webhook if you need to react to the final status. A Pending capture is not a failure.
Why didn't my line items or metadata reach Finix?
Level II and Level III data, metadata, and the shipping address have no equivalent in Finix's API, so they stay on the Preczn transaction and are not transmitted. Nothing else you send is altered — Finix imposes no length limits that would shorten a value.
Does a Verify charge the cardholder?
No. A Verify on Finix is run as a zero-dollar authorization, so no funds are captured and there is nothing to void afterward. It confirms the card is valid and returns AVS and CVV results.
Updated about 15 hours ago