Connect Erste (ex-Santander Bank Polska) accounts, BLIK and statements to your stack
The Erste mobile app — rebranded from Santander mobile during the April 2026 transition to Erste Bank Polska — concentrates the everyday banking surface of one of Poland's largest retail banks: balances, instant transfers, standing orders, BLIK codes, contactless payments, Erste Exchange FX, parking, motorway and public transport tickets, and the Erste Open ecosystem. We turn that surface into clean, programmable APIs.
Feature modules we expose as APIs
Accounts & balances
Full read access to current accounts, savings, cards and Mini Firma sole-proprietorship accounts. Includes available balance, accounting balance, blocked amounts and Smart Account fee progress as shown in Price advisor. Designed for treasury dashboards and reconciliation jobs that need a single source of truth for a Polish entity.
Transfers & standing orders
Domestic ELIXIR, Express ELIXIR instant transfers, SEPA and standing orders. The adapter mirrors the in-app two-factor mobile authorisation, so a backend caller still confirms each operation with a PIN, fingerprint or face challenge — keeping the integration aligned with PSD2 strong customer authentication (SCA).
BLIK & contactless
Generate BLIK codes, accept phone transfers via alias, withdraw cash from BLIK-enabled ATMs and pay in stores without a card. For Mini Firma customers, the same surface unlocks merchant-side BLIK acceptance, which is the cheapest acquiring path on the Polish market today.
Tickets, parking & tolls
Pay for motorway tolls, public transport tickets and parking, and top up games, music or office software directly from the customer's Erste account. The adapter normalises receipts so expense-management systems can attach them automatically to the right cost centre.
Insurance vault
Pull policy numbers and coverage periods that the app shows in the Insurance section. Useful for brokers building a single dashboard across multiple banks, or for B2B platforms that need to renew or cross-sell against existing coverage data.
Financial Coach & Subscriptions
Programmatic access to the spend chart and the Subscriptions tray, so analytics products can show monthly recurring spend per merchant without re-deriving categories from raw text. Pairs naturally with PSD2 AIS data from other Polish banks.
Data available for integration
The table below maps the Erste app surfaces to the data endpoints we typically expose. Granularity reflects what is realistically retrievable through PSD2 plus the authorised protocol adapter; everything is consent-gated and audit-logged.
| Data type | Source surface | Granularity | Typical use |
|---|---|---|---|
| Account list & metadata | "Your products" home tile | Per IBAN, currency, owner role | Treasury dashboards, KYC refresh |
| Transaction history | Statements / Financial Coach | Per-line with merchant, category, BLIK marker, counter-IBAN | Reconciliation, anti-fraud, ERP sync |
| Balance snapshots | Quick balance preview | Available + accounting, every 5 min | Cash-flow forecasting, liquidity alerts |
| BLIK code & phone transfer | BLIK screen | One-time 6-digit code, alias lookup | E-commerce checkout, P2P payouts |
| Standing orders & scheduled transfers | Transfers module | Amount, schedule, beneficiary | Subscription management, payroll |
| Subscriptions tray | Subscriptions widget | Merchant, monthly amount, currency | PFM apps, churn analytics |
| Card details & auth events | Card screen, Alerts24 | Masked PAN, expiry, last auths | Card-management UIs, 3DS auditing |
| Insurance policies | Insurance section | Policy number, coverage window | InsurTech consolidators, brokers |
| FX rates & Erste Exchange trades | Erste Exchange | Per-currency mid + spread, trade log | Treasury FX dashboards, hedging tools |
| Tickets, parking, motorway tolls | Pay-for-services tiles | Receipt per purchase, geo where present | Expense management, mobility apps |
Typical integration scenarios
1. Accounting sync for Mini Firma owners
A Polish sole-proprietorship platform pulls daily ELIXIR transactions from Erste through PSD2 AIS, attaches Mini Firma BLIK receipts via the protocol adapter, and posts journal entries to the customer's accounting backend. Fields used: booking_date, amount, currency, counter_iban, category, blik_ref. Maps to OpenBanking AIS plus an authorised value-added overlay.
2. BLIK checkout for e-commerce
A Polish marketplace uses the BLIK initiation endpoint to convert a guest cart into a paid order in under 8 seconds. The customer enters the one-time 6-digit code from the Erste app; the adapter forwards the code to PSP, confirms the transaction and emits an Alerts24-style webhook back to the shop. OpenFinance angle: instant pay-by-bank without card rails or 3DS friction.
3. Cross-CEE treasury dashboard
A regional CFO consolidates accounts across Erste Bank Polska, Erste Bank Croatia (Erste Open Banking) and Česká spořitelna using the shared Erste Developer Portal entry point. We deliver a normalised /accounts and /transactions contract on top, so each subsidiary feeds the same SAP dashboard.
4. PFM with Subscriptions and Financial Coach
A personal-finance app ingests Subscriptions and Financial Coach metrics through the protocol adapter, then overlays them on PSD2 transactions from mBank, ING and PKO IKO. The user sees a single spend chart across all Polish banks, with subscription-cancellation deep links back into Erste.
5. Compliance audit trail for fintech onboarding
An EMI onboarding flow uses the AIS endpoint to fetch 90 days of Erste statements, verifies salary credits, and stores a hashed PDF of the original statement as evidence. Our adapter ships the audit log fields (consent_id, scope, expiry, IP, SCA method) so compliance teams can answer regulator queries without re-pulling data.
Technical implementation
All adapters share a small surface: a token endpoint, resource endpoints, and a webhook endpoint. Below are three concrete examples — login, statement query, and a BLIK code request — taken from the patterns we ship in the source delivery.
Auth: mobile-authorised login
POST /api/v1/erste/auth/login
Content-Type: application/json
{
"login_id": "12345678",
"device_fingerprint": "<app-issued>",
"sca_method": "fingerprint"
}
201 Created
{
"access_token": "eyJhbGciOi...",
"refresh_token": "rt_8f2c...",
"expires_in": 900,
"consent_id": "cns_2026_05_10_a1",
"scopes": ["accounts.read", "transactions.read", "blik.initiate"]
}
Statement export with paging
POST /api/v1/erste/statement
Authorization: Bearer <ACCESS_TOKEN>
X-Consent-Id: cns_2026_05_10_a1
{
"iban": "PL61109010140000071219812874",
"from_date": "2026-04-01",
"to_date": "2026-04-30",
"page": 1,
"page_size": 100,
"include": ["blik_ref","category","counter_party"]
}
200 OK
{ "items": [ { "booking_date":"2026-04-12",
"amount":-129.90, "currency":"PLN",
"category":"subscriptions",
"counter_party":"Spotify AB",
"blik_ref": null } ],
"next_page": 2 }
BLIK code initiation
POST /api/v1/erste/blik/code
Authorization: Bearer <ACCESS_TOKEN>
{ "amount": 49.00, "currency": "PLN",
"purpose": "ecommerce_checkout",
"merchant_id": "M-77821" }
200 OK
{ "blik_code": "468123",
"ttl_seconds": 110,
"tx_id": "blik_tx_9912" }
# Webhook (Alerts24-style):
POST <your-callback>
{ "tx_id":"blik_tx_9912",
"status":"CONFIRMED",
"sca_method":"pin" }
Error handling follows RFC 7807 problem-details: {"type":"https://openfinance-lab.com/errors/sca-expired","title":"SCA expired","status":401}. Retries use exponential backoff capped at 30 seconds; idempotency keys are mandatory on every write endpoint to keep PSD2 anti-replay protections intact.
Compliance & privacy
Regulatory frame
Every Erste integration we ship is built against the Revised Payment Services Directive (PSD2) and its successor work (PSD3 / PSR currently in trilogue). On the Polish side we observe the Polish Banking Act, the Act on Payment Services, and the KNF (Polish Financial Supervision Authority) guidance for TPPs. GDPR Article 5 (data minimisation) and Article 6 (lawful basis) are part of the delivery checklist.
What we never store
Raw PINs, fingerprint templates and face-recognition vectors stay on the customer's device, exactly as the Erste app handles them. Our backend keeps only what is needed to honour the active consent: token hashes, consent metadata and the data the customer explicitly requested to retain. NDAs and DPAs are signed where requested.
Data flow / architecture
A typical Erste pipeline is four nodes deep:
- Erste mobile app / Erste developer portal — source of truth, with SCA enforced at the bank.
- OpenFinance Lab API gateway — handles consent registration, token refresh, rate limiting and audit logging.
- Storage layer — Postgres for normalised transactions, S3-compatible object store for archived statement PDFs, Redis for short-lived BLIK code state.
- Customer-facing surface — REST/JSON API, OpenAPI 3.1 spec, webhook fan-out for Alerts24-style events, plus optional GraphQL read view.
Each hop carries the consent_id and scope so a regulator-grade audit log can be reconstructed from any single transaction id.
Market positioning & user profile
Erste Bank Polska serves roughly 8 million retail and SME customers across 485 branches in Poland and is now part of Erste Group, which counts around 16 million customers across Central and Eastern Europe. The Erste app is predominantly B2C — retail current-account holders on Android and iOS — with a notable Mini Firma segment of sole proprietors using BLIK acceptance. International clients usually fall into three groups: (1) Polish e-commerce platforms that want BLIK checkout parity with PSP, (2) CEE-headquartered fintechs consolidating AIS across Erste Group subsidiaries, and (3) global treasury teams who keep a Polish subsidiary and need ELIXIR + SEPA visibility in one feed.
Screenshots
Tap any thumbnail to enlarge. Screenshots are taken from the Google Play listing for the current Erste app build.
Similar apps & integration landscape
The Polish digital banking market is one of the most competitive in Europe. Teams integrating Erste usually need to bridge to at least a few of the apps below; we maintain a similar adapter shape for each so a single PFM, treasury or e-commerce backend can target them with one contract.
mBank
mBank's app — historically a Polish UX benchmark — exposes detailed transaction history, the Mia spending assistant, mBroker brokerage and an internal FX exchange. Teams that integrate Erste often need parallel mBank exports so their PFM dashboards show a unified Polish view.
ING Bank Śląski (Moje ING)
Moje ING is known for minimalist flows and the 2026-added "Goals" savings automation. Its PSD2 AIS feed pairs naturally with Erste's, especially for cross-bank salary-credit verification used by Polish EMIs.
PKO Bank Polski — IKO
IKO holds the highest user count among Polish banking apps and integrates mObywatel, ePUAP, ZUS and e-prescription flows. Combining IKO and Erste data unlocks "single-citizen" dashboards for govtech and HR-tech vendors.
Pekao — PeoPay
PeoPay's 2026 redesign added spending analytics and tighter BLIK flows. As a peer of Erste in the top-tier of Polish banks, it's frequently the second feed treasury teams ask for after Erste.
Millennium Bank
Millennium added a lock-screen financial summary widget and Apple Watch BLIK in 2026. Often paired with Erste in PFM aggregators that target the urban under-35 segment.
Alior Bank
Alior — one of the six founding BLIK shareholders alongside the original Bank Zachodni WBK / Santander / Erste lineage — exposes consumer lending data and is a common counter-party for credit-aggregator products built on top of Erste statements.
BNP Paribas — GOonline / GOmobile
BNP's Polish app is widely used by SMEs and freelancers. Pairing it with Erste's Mini Firma data is a typical setup for accounting-automation vendors operating across mid-market segments.
Revolut Poland
Revolut runs as an EMI in Poland and is the dominant non-bank wallet. Customers usually want unified statements that merge Revolut spend with their primary Erste current account, including FX P&L from Erste Exchange.
BLIK (Polski Standard Płatności)
BLIK is the dominant Polish payment scheme — six-digit codes, P2P by phone number, ATMs and merchants. Erste's BLIK endpoint plugs straight into the same rails, so an integration here is also an integration with the wider BLIK ecosystem.
About our studio
What we are
We're an independent engineering studio focused on app protocol analysis and authorised API integration. Our engineers have shipped fintech back ends in Polish, German and pan-EU banks, run AIS/PIS sandboxes against the Erste Developer Portal and PolishAPI, and built BLIK-acceptance integrations for e-commerce platforms.
- PSD2 AIS / PIS adapters for CEE and Western European banks
- BLIK initiation and acceptance pipelines, with PSP-compatible code handling
- Protocol adapters that mirror official app flows under user consent
- Custom Python, Node.js and Go SDKs plus pytest / vitest test harnesses
- End-to-end pipeline: research → protocol analysis → build → validation → compliance handover
- Source code delivery from $300 — runnable API source code and full documentation; pay after delivery upon satisfaction
- Pay-per-call API billing — access our hosted endpoints and pay only per call, no upfront cost; ideal for teams that prefer usage-based pricing
Contact
For a quote on the Erste app or any of the similar apps listed above, send us the target slug and your concrete requirements (data types, expected QPS, region, hosting model). We'll respond within one business day.
What we deliver
Deliverables checklist
- OpenAPI 3.1 specification covering accounts, transactions, BLIK and webhooks
- Protocol & auth flow report — token chain, SCA challenge format, error catalogue
- Runnable source for login, statement, BLIK and Alerts24 endpoints (Python and Node.js)
- Pytest / Vitest test harness plus a Postman collection
- Compliance pack: PSD2 alignment notes, GDPR data-minimisation matrix, KNF references
- One-on-one handover session with the customer's engineering team
Engagement workflow
- Scope confirmation — which Erste surfaces, which volumes, which hosting model (1-2 days).
- Protocol analysis & API design against the Erste Developer Portal and the current app build (2-5 days).
- Build & internal validation in our sandbox (3-8 days).
- Docs, samples, test cases and security review (1-2 days).
- Typical first delivery: 5-15 business days; multi-bank or PSD3-readiness work can extend the timeline.
FAQ
Do you integrate against the official Erste PSD2 APIs or via app-protocol analysis?
Does the integration still work after the Santander-to-Erste rebrand?
pl.bzwbk.bzwbk24 across the April 2026 rebrand, and existing account numbers, card numbers and contracts were preserved. Login flows still target the Santander mobile back end, now reachable via erste.pl domains; our adapters track both hostnames during the transition window.How long does a first delivery take?
How do you handle GDPR and Polish banking-secrecy rules?
Original app overview — Erste (formerly Santander mobile)
In the Erste app you'll find everything you need for everyday banking: your account balance, transfers (including instant transfers and standing orders), your products, BLIK, Erste Open, the Erste Exchange, contactless payments, and the bank's full offer.
Make the app your own. Tell the bank how it should address you and choose your wallpaper. Stay private in public places — tap the eye icon on the home screen to switch on Discreet Mode, perfect for moments when you're, for example, on a tram and don't want others to see your balance.
Keep track of what's happening on your account and card thanks to Alerts24 and quick balance preview. Financial Coach gives you a clear chart of your spending and income, and in Subscriptions you can see how much you pay monthly across your services. Price advisor shows you how close you are to paying 0 PLN for the Smart Account and your monthly card fee.
In the app you can also check your card details, pay for parking or motorway tolls, buy public transport tickets, and top up games, movies, music or office apps. You'll also find information about your insurance, including policy numbers and coverage periods.
For even greater security, when activating the app the bank will ask you to enable mobile authorisation. You'll confirm operations in the app and online banking with a 4-digit PIN, fingerprint or face recognition. You log in to the app with one single login. On the login screen the app shows services linked to that account (e.g. quick preview, BLIK, tickets, parking), which is why multiple people cannot use the same app. If you need to use another login, you can do so in your mobile browser by logging in to online banking.
If you have a sole proprietorship and use Mini Firma online banking, you can use BLIK in the app: withdraw cash from BLIK-enabled ATMs, make phone transfers and pay in stores without a card or cash. The Erste app was previously called Santander mobile. More information about the app: erste.pl/aplikacja.