Bring Prime Financial Credit Union member data into your accounting, CRM, and risk stack
The Prime Mobile App (package com.primefinancial.mobilebanking) is the daily channel for thousands of credit-union members in the Milwaukee region. We deliver authorized, audit-friendly APIs that mirror what members see in the app: share and draft balances, posted and pending transactions, loan payoffs, mobile remote deposit (RDC) receipts, instant person-to-person sends, and account-activity alerts.
What we deliver
Deliverables checklist
- OpenAPI 3.1 specification covering auth, balances, transactions, transfers, RDC, alerts
- Protocol report: login flow, token rotation, device-binding, and certificate-pinning notes
- Runnable source code in Python (FastAPI) or Node.js (NestJS), plus a thin Go client
- FDX-compatible payload mappers so output can be shipped straight to aggregators or BI tools
- Postman collection, integration tests against a sandbox account, and webhook simulators
- Compliance pack: member-consent template, retention schedule, audit-log schema, NCUA/GLBA notes
What sets this engagement apart
Credit unions are not banks. Membership eligibility, joint-owner rules, share-vs-deposit terminology and loan-account structures all differ from a retail bank, and a generic Plaid wrapper hides those details. Our adapter preserves credit-union semantics — share numbers, suffixes, loan ledger types — so accounting and analytics consumers see the same hierarchy a teller sees.
Every integration ships with a member-impersonation switch off by default. Production calls require either a member-issued OAuth-style token or a documented aggregator key. Nothing reads the app's private endpoints without an audit trail.
Data available for integration
The Prime Mobile App surfaces a defined set of member records. The table below maps each record to the screen it comes from, the granularity we expose, and a typical downstream use. Field names follow the FDX 5.x convention where possible so existing OpenBanking consumers can pick the feed up without remodeling.
| Data type | Source (app screen / feature) | Granularity | Typical use |
|---|---|---|---|
| Share & draft balances | Accounts dashboard, account detail | Per share/sub-account; current & available | Cash-flow forecasting, multi-bank dashboards |
| Loan balances & payoff | Loans tab, loan detail | Principal, accrued interest, next-due date, payoff amount | Loan reconciliation, refinance offers, debt advice tools |
| Posted transactions | Transaction history | ISO date, amount, merchant, MCC, channel, ID | Bookkeeping, expense categorization, fraud monitoring |
| Pending authorizations | Transaction history (pending tab) | Authorization hold, merchant, expected post date | Real-time available-funds, treasury overlays |
| RDC receipts | Deposit checks (camera) | Front/back image hashes, amount, funds-availability date | Audit log, receipt archival, AR matching |
| P2P / A2A transfers | Transfer / Send Money | Source, destination, amount, status, network | Payroll reconciliation, member-to-member analytics |
| Account-activity alerts | Alerts / notifications | Event type, threshold, channel (push, email, SMS) | Ops monitoring, treasury sweeps, fraud triage |
| Secure member messages | Message center | Thread, timestamp, attachments meta | Support handoff into Zendesk/Salesforce |
Typical integration scenarios
1. Multi-institution cash-flow dashboard
A small-business member runs payroll out of Prime Financial CU and holds working capital at another institution. We sync nightly balances and posted transactions from /v1/accounts and /v1/transactions, normalize them to FDX, and push into a single QuickBooks / Xero ledger. OpenFinance framing: read-only personal financial data under member consent, refreshable on a 4-hour cadence.
2. Loan-officer payoff & refinance workflow
A fintech wants to offer balance-transfer refis to Prime Financial CU members. With member-issued tokens, the partner calls /v1/loans/{id}/payoff for a real-time payoff figure and uses /v1/transactions?account_type=LOAN to validate 12 months of on-time payments. Output feeds an underwriting model that returns a personalised APR.
3. Mobile deposit reconciliation for AR teams
An accounting firm matches RDC receipts to invoices. We listen for deposit.submitted and deposit.cleared webhooks (within Prime Financial's $2,000/check, $5,000/day RDC envelope) and reconcile each cleared item against an invoice ID encoded in the memo line. Funds typically become available within two business days.
4. Treasury alert pipeline
A treasury team needs Slack pings when a share balance falls below a sweep threshold or when a large debit posts. We translate Prime Mobile App alerts into a webhook bus and emit signed events to Slack, PagerDuty, or any HTTP receiver. This replaces a fragile screen-scraping job with an OpenBanking-style alert feed.
5. KYC refresh & activity scoring
A regtech consumes member transaction patterns and basic profile fields to keep KYC profiles current under NCUA member-data guidance. Output is a daily activity score; PII is hashed before leaving our pipeline, and the credit union retains the full audit log of every consent and read.
Technical implementation
Authentication & session
POST /v1/pfcu/auth/login
Content-Type: application/json
{
"member_number": "0001234567",
"credential": "<PIN_OR_PASSCODE>",
"device_id": "ios:5C9F-...-A2",
"mfa_token": "123456"
}
200 OK
{
"access_token": "eyJhbGciOi...",
"refresh_token": "rt_8a...",
"expires_in": 1800,
"scope": ["accounts:read","tx:read","transfer:write","rdc:write"]
}
Statement / transaction query
GET /v1/pfcu/transactions?account_id=S0001-00&from=2026-04-01&to=2026-04-30&page=1
Authorization: Bearer <ACCESS_TOKEN>
200 OK
{
"account_id": "S0001-00",
"currency": "USD",
"page": 1, "page_size": 100, "has_more": false,
"items": [
{"id":"tx_01HX...","posted_at":"2026-04-29T14:02:11Z",
"amount":-42.18,"merchant":"KWIK TRIP #421","mcc":"5411",
"channel":"DEBIT_POS","status":"POSTED"},
{"id":"tx_01HX...","posted_at":"2026-04-28T10:11:00Z",
"amount":1500.00,"merchant":"PAYROLL ACME LLC","mcc":null,
"channel":"ACH_CREDIT","status":"POSTED"}
]
}
RDC submit + webhook
POST /v1/pfcu/rdc/deposit
Authorization: Bearer <ACCESS_TOKEN>
Content-Type: multipart/form-data
front=<jpeg> back=<jpeg> amount=125.40 account_id=S0001-00
202 Accepted
{"deposit_id":"rdc_42","status":"PENDING_REVIEW",
"limit_check":{"per_check":2000,"daily_remaining":4874.60}}
# Asynchronous callback
POST https://your.app/webhooks/pfcu
X-Signature: sha256=...
{
"event": "deposit.cleared",
"deposit_id": "rdc_42",
"available_on": "2026-05-01",
"amount": 125.40
}
Error handling, retries & idempotency
All write endpoints accept an Idempotency-Key header and return the same response for replays within 24 hours. Read endpoints back off with exponential retry on 429 and 5xx codes. We surface a stable error envelope {"error":{"code":"...","message":"...","retryable":bool}} so client code does not have to learn institution-specific messages.
Compliance & privacy
Regulatory framing
Integrations are scoped to the United States and align with the CFPB Section 1033 Personal Financial Data Rights rule finalized on 22 October 2024. The largest covered institutions begin compliance on 1 April 2026; smaller credit unions follow on a tiered schedule through 2030. We also follow GLBA safeguards, NCUA member-data guidance, and the FDX schema for portable payloads.
Privacy controls baked in
- Member consent recorded per scope and per partner, revocable from a single endpoint
- Field-level masking (full PAN, full SSN never leave the secure boundary)
- Daily audit export with caller, scope, IP, and rows returned
- Optional on-prem deployment when the credit union prefers to keep keys in-house
- Right-to-delete workflow for closed-account data, 7-day default purge for cached payloads
Data flow & architecture
The pipeline is intentionally small so it can sit behind a single VPC:
- Prime Mobile App / aggregator endpoint — source of truth, reached under member consent.
- Ingestion gateway — handles auth, MFA token rotation, retries, certificate pinning.
- Normaliser — converts native payloads to FDX-shaped JSON and tags PII for masking.
- Storage & egress — short-lived Postgres cache + S3 for RDC images, then REST/webhook out to your consumers.
The same code path serves both delivery modes: source-code drop (you host the gateway) and pay-per-call (we host it for you).
Market positioning & user profile
Prime Financial Credit Union is a member-owned cooperative headquartered in Milwaukee, Wisconsin, with branches across Milwaukee, Brown Deer and Cudahy. Its mobile users are predominantly Wisconsin residents in retail, education and small-business roles who use the app as their day-to-day banking channel rather than as a secondary tool. Platform mix is roughly even between Android and iOS, with a long tail of older devices — meaning any integration must remain compatible with mature mobile OS releases. The credit union sits in the same competitive cluster as community-focused institutions and large nationwide credit unions, which makes a unified API export especially valuable for members who hold accounts across more than one cooperative.
Screenshots
Tap any thumbnail to enlarge. These screens illustrate the surfaces our API mirrors — dashboards, transactions, transfers, deposits and alerts.
Similar apps & the integration landscape
Members who use Prime Financial CU often hold accounts at one of the apps below. We frame these purely as part of the broader OpenBanking landscape — the same integration patterns described above apply, with institution-specific quirks.
- Navy Federal Credit Union — Largest U.S. credit union; integration partners often need a single export covering Navy Federal and a local cooperative like Prime Financial CU.
- Alliant Credit Union — Nationwide digital-first credit union with a similar feature set (balances, RDC, P2P) and a comparable mobile data model.
- PenFed Credit Union — Membership open through several routes; loan-focused data flows align well with the payoff and refinance scenarios above.
- BECU — Boeing-employee origins, now serving Washington residents; transaction and alert payloads map cleanly into the same FDX shape.
- Digital Federal Credit Union (DCU) — Strong tech focus; users frequently want unified exports across DCU and a Midwestern cooperative.
- Bank of America Mobile Banking — Large retail bank counterparty for joint households; many members operate with both accounts side-by-side.
- Chase Mobile — Often paired with a credit-union account for business workflows that require a national bank for ACH origination.
- Capital One Mobile — Common as a secondary credit-card and savings provider; transaction sync into the same dashboard is a frequent request.
- Discover Mobile — Card-centric data feed that pairs well with the credit-union checking account on the budgeting side.
- USAA Mobile — Member-driven institution with a similar cooperative ethos; multi-institution dashboards routinely span USAA and a regional credit union.
About us
OpenFinance Lab is an independent studio focused on mobile-app protocol analysis and OpenBanking-style API integration. Our engineers have shipped production data pipelines for banks, credit unions, payment networks and fintech aggregators across North America, Europe and Asia.
- Member-permissioned access only — no scraping without a documented consent trail
- Familiar with NCUA, CFPB §1033, GLBA, PCI-DSS and FDX patterns
- Source-code drop in Python / Node / Go, plus optional hosted API
- End-to-end: protocol analysis → build → validation → compliance review
- Source-code delivery from $300 — pay on satisfaction after delivery
- Pay-per-call billing — no upfront cost, ideal for teams that prefer usage-based pricing
Contact
To request a quote or scope a Prime Financial Credit Union integration, open our contact page and tell us which endpoints you need first.
Engagement workflow
- Scope confirmation: which Prime Mobile App surfaces and member-data scopes are required.
- Protocol analysis and API design (2–5 business days).
- Build, sandbox validation and FDX mapping (3–8 business days).
- Docs, Postman collection, sample apps and test cases (1–2 business days).
- Typical first delivery: 5–15 business days; aggregator approval may extend this.
FAQ
Does Prime Financial Credit Union publish a public developer API?
What member-level data can be exposed to my back office?
How long does a first delivery take and what does it cost?
Is this approach compliant with U.S. open banking rules?
📱 Original app overview (appendix)
The Prime Mobile App puts secure online banking in the palm of your hand anywhere, anytime — at the grocery store, on a well-deserved vacation, or doing some late-night shopping — with peace of mind that members can manage their finances on the go.
What the app enables members to do:
- Check account & loan balances
- Transfer funds between accounts
- Deposit checks with the device's camera (up to $2,000 per check, $5,000 per day; funds typically available within two business days)
- Create account-activity alerts
- Make loan payments
- Send money instantly to others
- View transaction history
- Securely send messages to the Member Support Center
- And more — eDocuments, card management, credit monitoring, spend tracking, and bill pay are available through the wider digital banking platform
The Prime Mobile App is available exclusively for members of Prime Financial Credit Union, a Milwaukee-based cooperative serving Milwaukee, Brown Deer and Cudahy, Wisconsin. Non-members can learn about joining at www.primefinancialcu.org or by calling 800.835.9680.