🕒 15 minute read
Fixed Periodic Schedule — API Guide v2.1
A Fixed Periodic Schedule consent authorises a TPP to initiate one payment per period at a fixed amount over the lifetime of the consent. The user authorises once — approving a specific payment amount and the recurring period — and the TPP submits one payment per period without requiring re-authorisation each time.
Common use cases include fixed monthly subscriptions, regular instalment collection, and recurring membership fees where the charge is always the same and payments follow a predictable calendar.
Prerequisites
Before initiating a Fixed Periodic Schedule payment, ensure the following requirements are met:
Registered Application The application must be created within the Trust Framework and assigned the BSIP role as defined in Roles.
Valid Transport Certificate An active transport certificate must be issued and registered in the Trust Framework to establish secure mTLS communication.
Valid Signing Certificate An active signing certificate must be issued and registered in the Trust Framework. This certificate is used to sign request objects and client assertions.
Registration with the relevant Authorisation Server The application must be registered with the Authorisation Server of the LFI with which you intend to initiate payments.
Understanding of the FAPI Security Profile and Tokens & Assertions You should understand how request object signing, client authentication, and access token validation underpin secure API interactions.
Understanding of Message Encryption PII (creditor name and account details) must be encrypted as a JWE before being embedded in the consent. You will need the LFI's public encryption key from their JWKS.
API Sequence Flow
POST /par
Step 1 - Encrypting PII
The consent.PersonalIdentifiableInformation property in the authorization_details carries sensitive payment data — creditor account details, debtor information, and risk indicators. Because consents are stored centrally at Nebras, this data is encrypted end-to-end so that no intermediate party can read it.
The schema defines PersonalIdentifiableInformation as a oneOf with three variants:
| Variant | Form | Notes |
|---|---|---|
| Domestic Payment PII Schema Object | object | Unencrypted form — shows the PII structure for domestic payments. For reference only. |
| International Payment PII Schema Object | object | Unencrypted form — shows the PII structure for international payments. For reference only. |
Encrypted PII Object (AEJWEPaymentPII) | string | Compact JWE string. MUST be used when invoking the PAR operation. |
Domestic Payment PII Schema Object must be strictly followed
The object you encrypt MUST conform exactly to the Domestic Payment PII Schema Object. Field names, nesting, and data types are validated by the LFI after decryption — any deviation will result in payment rejection. Do not add undocumented fields or omit required ones.
See Personal Identifiable Information for the complete field reference, required vs optional fields, and creditor models for each domestic payment type.
Creditor array — exactly one entry
Initiation.Creditor is an array but must contain exactly one entry for this payment type. The consent is bound to that single recipient — every payment made under this consent must go to that account.
See Creditor for the field schema and validation rules.
The PII object is serialized to JSON, signed as a JWS using your signing key, and then encrypted as a JWE using the LFI's public encryption key — producing the AEJWEPaymentPII compact string embedded as PersonalIdentifiableInformation in the consent.
Encrypting the PII
Build the PII object according to the schema, then encrypt it as a JWE using the LFI's public encryption key:
import { SignJWT, importJWK, CompactEncrypt } from 'jose'
/**
* Sign PII as a JWT and encrypt it as a JWE using the LFI's public encryption key.
* Fetch the LFI's JWKS URI from their .well-known/openid-configuration.
*/
async function encryptPII(pii: object, jwksUri: string, signingKey: CryptoKey, signingKeyId: string): Promise<string> {
// 1. Sign the PII as a JWT
const signedPII = await new SignJWT(pii as Record<string, unknown>)
.setProtectedHeader({ alg: 'PS256', kid: signingKeyId })
.sign(signingKey)
// 2. Fetch the LFI's encryption key
const { keys } = await fetch(jwksUri).then(r => r.json())
const encKeyJwk = keys.find((k: { use: string }) => k.use === 'enc')
if (!encKeyJwk) throw new Error('No encryption key (use: enc) found in JWKS')
const encKey = await importJWK(encKeyJwk, 'RSA-OAEP-256')
// 3. Encrypt the signed JWT
return new CompactEncrypt(new TextEncoder().encode(signedPII))
.setProtectedHeader({
alg: 'RSA-OAEP-256',
enc: 'A256GCM',
kid: encKeyJwk.kid,
})
.encrypt(encKey)
}
const pii = {
"Initiation": {
"DebtorAccount": {
"SchemeName": "IBAN",
"Identification": "AE070331234567890123456",
"Name": {
"en": "Mohammed Al Rashidi",
}
},
"Creditor": [
{
"Creditor": {
"Name": "Ivan England"
},
"CreditorAccount": {
"SchemeName": "IBAN",
"Identification": "AE070331234567890123456",
"Name": {
"en": "Ivan David England"
}
}
}
]
}
}
const encryptedPII = await encryptPII(pii, LFI_JWKS_URI, signingKey, SIGNING_KEY_ID)
// encryptedPII is a compact JWE string — embed it in authorization_details belowimport json
import requests
from jose import jwe
def encrypt_pii(pii: dict, jwks_uri: str) -> str:
keys = requests.get(jwks_uri).json()["keys"]
enc_key = next((k for k in keys if k.get("use") == "enc"), None)
if not enc_key:
raise ValueError("No encryption key (use: enc) found in JWKS")
return jwe.encrypt(
json.dumps(pii).encode(),
enc_key,
algorithm="RSA-OAEP-256",
encryption="A256GCM",
).decode()
pii = {
"Initiation": {
"DebtorAccount": {
"SchemeName": "IBAN",
"Identification": "AE070331234567890123456",
"Name": {
"en": "Mohammed Al Rashidi",
}
},
"Creditor": [
{
"Creditor": {
"Name": "Ivan England"
},
"CreditorAccount": {
"SchemeName": "IBAN",
"Identification": "AE070331234567890123456",
"Name": {
"en": "Ivan David England"
}
}
}
]
},
}
encrypted_pii = encrypt_pii(pii, LFI_JWKS_URI)
# encrypted_pii is a compact JWE string — embed it in authorization_details belowSee Message Encryption for details on fetching the LFI's JWKS and selecting the correct encryption key.
Step 2 - Constructing Authorization Details
With the encrypted PII ready, construct the authorization_details of type urn:openfinanceuae:service-initiation-consent:v2.1. Set PeriodicSchedule.Type to "FixedPeriodicSchedule". The payment amount is fixed at consent time via PeriodicSchedule.Amount — every POST /payments call under this consent must use exactly this amount, and only one payment may be submitted per period.
authorization_details
| Field | Type | Description | Example |
|---|---|---|---|
type* | enum | Must be urn:openfinanceuae:service-initiation-consent:v2.1 | urn:openfinanceuae:service-initiation-consent:v2.1 |
consent* | object | Consent properties agreed by the User with the TPP. Described below | — |
subscription | object | Optional subscription to Event Notifications via Webhook. Described below | — |
consent (Required) | authorization_details.consent
| Field | Type | Description | Example |
|---|---|---|---|
ConsentId* | string (uuid) | Unique ID assigned by the TPP (1–128 chars) | b8f42378-10ac-46a1-8d20-4e020484216d |
IsSingleAuthorization* | boolean | Whether the payment requires only one authorizing party | true |
ExpirationDateTime* | date-time | Consent expiry (ISO 8601 with timezone, max 1 year) | 2027-03-02T00:00:00+00:00 |
AuthorizationExpirationDateTime | date-time | Deadline by which all authorizers must have acted (multi-authorization only). SHOULD be set when IsSingleAuthorization is false; SHOULD NOT be set when IsSingleAuthorization is true. MUST NOT be after ExpirationDateTime. | 2026-03-03T10:00:00+00:00 |
BaseConsentId | string (uuid) | Links to prior consent if renewing — see Base Consent ID | — |
Permissions | array<enum> | Optional access permissions granted alongside the payment consent | ReadAccountsBasic, ReadBalances |
ControlParameters* | object | Payment controls — see below | — |
PersonalIdentifiableInformation* | string (JWE) | Encrypted creditor and risk data — the encryptedPII string from Step 1 | eyJhbGci... |
PaymentPurposeCode* | string (3 chars) | AANI payment purpose code | ACM |
DebtorReference | string | Reference shown on the debtor's statement | Subscription |
CreditorReference | string | Reference shown on the creditor's statement | Subscription |
ControlParameters — Fixed Periodic Schedule
ControlParameters.ConsentSchedule.MultiPayment carries the control definition. Set PeriodicSchedule.Type to "FixedPeriodicSchedule". Only one payment is permitted per period. There is no Controls block — the period itself acts as the limiting boundary.
Cumulative Control Parameters — apply across the entire consent lifetime:
| Field | Required | Description | Example |
|---|---|---|---|
MaximumCumulativeNumberOfPayments | Yes | Maximum total number of payments over the consent lifetime | 24 |
MaximumCumulativeValueOfPayments.Amount | No | Maximum total value of all payments over the consent lifetime | 3600.00 |
MaximumCumulativeValueOfPayments.Currency | No | ISO 4217 currency code | AED |
Periodic Schedule Parameters — define the fixed amount and period, set directly inside PeriodicSchedule:
| Field | Required | Description | Example |
|---|---|---|---|
PeriodicSchedule.PeriodType | Yes | The period length: Day, Week, Month, or Year | Month |
PeriodicSchedule.PeriodStartDate | Yes | The date from which each period is counted. Must be in the future (today is rejected) and before ExpirationDateTime | 2027-01-01 |
PeriodicSchedule.Amount.Amount | Yes | The fixed payment amount. Every payment submitted under this consent must be for exactly this value | 150.00 |
PeriodicSchedule.Amount.Currency | Yes | ISO 4217 currency code | AED |
One payment per period
Only one payment may be submitted per period. The API Hub will reject a second POST /payments call within the same period, even if the amount matches.
Example request
"authorization_details": [
{
"type": "urn:openfinanceuae:service-initiation-consent:v2.1",
"consent": {
"ConsentId": "{{unique-guid}}",
"IsSingleAuthorization": true,
"ExpirationDateTime": "2027-03-02T00:00:00+00:00",
// Multi-authorization only: deadline for all authorizers to act.
// SHOULD NOT be set when IsSingleAuthorization is true.
// "AuthorizationExpirationDateTime": "2026-03-03T10:00:00+00:00",
"Permissions": [
"ReadAccountsBasic",
"ReadAccountsDetail",
"ReadBalances"
],
"ControlParameters": {
"ConsentSchedule": {
"MultiPayment": {
"MaximumCumulativeNumberOfPayments": 24,
// Optional consent-lifetime cumulative value cap:
// "MaximumCumulativeValueOfPayments": { "Amount": "3600.00", "Currency": "AED" },
"PeriodicSchedule": {
"Type": "FixedPeriodicSchedule",
"PeriodType": "Month",
"PeriodStartDate": "2027-01-01",
"Amount": { "Amount": "150.00", "Currency": "AED" }
}
}
}
},
// Encrypted PII from Step 1
"PersonalIdentifiableInformation": "{{encryptedPII}}",
"PaymentPurposeCode": "ACM",
"DebtorReference": "Subscription",
"CreditorReference": "Subscription"
}
}
]Step 3 - Constructing the Request JWT
With your authorization_details ready, generate a PKCE code pair then use the buildRequestJWT() helper, passing payments openid as the scope.
Scope change required when using Permissions
If your consent includes ReadAccountsBasic, ReadAccountsDetail, or ReadBalances, you must change the scope to accounts payments openid. Without the accounts scope the issued token will not grant access to the account endpoints. You will also need the BDSP role. See Account Permissions in a Payment Consent.
import crypto from 'node:crypto'
import { generateCodeVerifier, deriveCodeChallenge } from './pkce'
import { buildRequestJWT } from './request-jwt'
const codeVerifier = generateCodeVerifier()
const codeChallenge = deriveCodeChallenge(codeVerifier)
const authorizationDetails = [
{
type: 'urn:openfinanceuae:service-initiation-consent:v2.1',
consent: {
ConsentId: crypto.randomUUID(),
IsSingleAuthorization: true,
ExpirationDateTime: new Date(Date.now() + 364 * 24 * 60 * 60 * 1000).toISOString(),
Permissions: ['ReadAccountsBasic', 'ReadAccountsDetail', 'ReadBalances'],
ControlParameters: {
ConsentSchedule: {
MultiPayment: {
MaximumCumulativeNumberOfPayments: 24,
// Optional consent-lifetime cumulative value cap:
// MaximumCumulativeValueOfPayments: { Amount: '3600.00', Currency: 'AED' },
PeriodicSchedule: {
Type: 'FixedPeriodicSchedule',
PeriodType: 'Month',
PeriodStartDate: '2027-01-01',
Amount: { Amount: '150.00', Currency: 'AED' },
},
},
},
},
PersonalIdentifiableInformation: encryptedPII, // from Step 1
PaymentPurposeCode: 'ACM',
DebtorReference: 'Subscription',
CreditorReference: 'Subscription',
},
},
]
const requestJWT = await buildRequestJWT({
scope: 'payments openid',
codeChallenge,
authorizationDetails,
})import uuid
from datetime import datetime, timezone, timedelta
from pkce import generate_code_verifier, derive_code_challenge
from request_jwt import build_request_jwt
code_verifier = generate_code_verifier()
code_challenge = derive_code_challenge(code_verifier)
authorization_details = [
{
"type": "urn:openfinanceuae:service-initiation-consent:v2.1",
"consent": {
"ConsentId": str(uuid.uuid4()),
"IsSingleAuthorization": True,
"ExpirationDateTime": (datetime.now(timezone.utc) + timedelta(days=364)).isoformat(),
"Permissions": ["ReadAccountsBasic", "ReadAccountsDetail", "ReadBalances"],
"ControlParameters": {
"ConsentSchedule": {
"MultiPayment": {
"MaximumCumulativeNumberOfPayments": 24,
# Optional consent-lifetime cumulative value cap:
# "MaximumCumulativeValueOfPayments": {"Amount": "3600.00", "Currency": "AED"},
"PeriodicSchedule": {
"Type": "FixedPeriodicSchedule",
"PeriodType": "Month",
"PeriodStartDate": "2027-01-01",
"Amount": {"Amount": "150.00", "Currency": "AED"},
},
}
}
},
"PersonalIdentifiableInformation": encrypted_pii, # from Step 1
"PaymentPurposeCode": "ACM",
"DebtorReference": "Subscription",
"CreditorReference": "Subscription",
},
}
]
request_jwt = build_request_jwt(
scope="payments openid",
code_challenge=code_challenge,
authorization_details=authorization_details,
)Store the code_verifier
Save codeVerifier in your server-side session or an httpOnly cookie — you will need it in Step 8 to exchange the authorization code for tokens.
See Preparing the Request JWT for the full JWT claim reference and PKCE helpers.
Step 4 - Creating a Client Assertion
Use the signJWT() helper to build a client assertion proving your application's identity:
import crypto from 'node:crypto'
import { signJWT } from './sign-jwt'
const CLIENT_ID = process.env.CLIENT_ID!
const ISSUER = process.env.AUTHORIZATION_SERVER_ISSUER!
async function buildClientAssertion(): Promise<string> {
return signJWT({
iss: CLIENT_ID,
sub: CLIENT_ID,
aud: ISSUER,
jti: crypto.randomUUID(),
})
}import os
import uuid
from sign_jwt import sign_jwt
CLIENT_ID = os.environ["CLIENT_ID"]
ISSUER = os.environ["AUTHORIZATION_SERVER_ISSUER"]
def build_client_assertion() -> str:
return sign_jwt({
"iss": CLIENT_ID,
"sub": CLIENT_ID,
"aud": ISSUER,
"jti": str(uuid.uuid4()),
})See Client Assertion for the full claims reference.
Step 5 - Sending the /par Request
Include x-fapi-interaction-id on the request — the API Hub echoes it in the response for end-to-end traceability. See Request Headers.
import crypto from 'node:crypto'
// PAR endpoint is read from .well-known/openid-configuration —
// not constructed from the issuer URL (it lives on a different host).
const PAR_ENDPOINT = discoveryDoc.pushed_authorization_request_endpoint
const parResponse = await fetch(PAR_ENDPOINT, {
method: 'POST',
headers: {
'Content-Type': 'application/x-www-form-urlencoded',
'x-fapi-interaction-id': crypto.randomUUID(),
},
body: new URLSearchParams({
request: requestJWT,
client_assertion_type: 'urn:ietf:params:oauth:client-assertion-type:jwt-bearer',
client_assertion: await buildClientAssertion(),
}),
// agent: new https.Agent({ cert: transportCert, key: transportKey }),
})
const { request_uri, expires_in } = await parResponse.json()import httpx, uuid
# PAR endpoint is read from .well-known/openid-configuration —
# not constructed from the issuer URL (it lives on a different host).
par_endpoint = discovery_doc["pushed_authorization_request_endpoint"]
par_response = httpx.post(
par_endpoint,
headers={
"x-fapi-interaction-id": str(uuid.uuid4()),
},
data={
"request": request_jwt,
"client_assertion_type": "urn:ietf:params:oauth:client-assertion-type:jwt-bearer",
"client_assertion": build_client_assertion(),
},
# cert=("transport.crt", "transport.key"),
)
data = par_response.json()
request_uri = data["request_uri"]
expires_in = data["expires_in"]mTLS transport certificate
You must present your transport certificate on every connection to the Authorization Server and resource APIs. See Certificates.
| Field | Description | Example |
|---|---|---|
request_uri | Single-use reference to your pushed authorization request | urn:ietf:params:oauth:request-uri:bwc4JDpSd7 |
expires_in | Seconds until the request_uri expires — redirect the user before this window closes | 90 |
Redirecting the User to the Bank
Step 6 - Building the Authorization URL
The authorization_endpoint is found in the LFI's .well-known/openid-configuration — not constructed from the issuer URL directly.
// authorization_endpoint from .well-known/openid-configuration
// Each LFI sets its own path — there is no fixed structure
// e.g. on the altareq1 sandbox: 'https://auth1.altareq1.sandbox.apihub.openfinance.ae/auth'
const AUTHORIZATION_ENDPOINT = discoveryDoc.authorization_endpoint
const authCodeUrl = `${AUTHORIZATION_ENDPOINT}?client_id=${CLIENT_ID}&response_type=code&scope=openid&request_uri=${encodeURIComponent(request_uri)}`
window.location.href = authCodeUrl
// or server-side: res.redirect(authCodeUrl)import urllib.parse
AUTHORIZATION_ENDPOINT = discovery_doc["authorization_endpoint"]
auth_code_url = (
f"{AUTHORIZATION_ENDPOINT}"
f"?client_id={CLIENT_ID}"
f"&response_type=code"
f"&scope=openid"
f"&request_uri={urllib.parse.quote(request_uri)}"
)
# redirect the user to auth_code_urlAfter redirecting, the user will see the bank's authorization screen showing:
- The TPP name and purpose
- The fixed payment
Amount(e.g. "AED 150.00 per payment") - The period type and start date (e.g. "Monthly from 1 March 2026")
- Any lifetime cumulative caps
- The consent expiry date
User Experience
See User Experience for screen mockups of the Fixed Periodic Schedule Consent and Authorization pages the user sees at the bank.
Handling the Callback
Step 7 - Extracting the Authorization Code
After the user approves, the bank redirects to your redirect_uri:
https://yourapp.com/callback?code=fbe03604-baf2-4220-b7dd-05b14de19e5c&state=d2fe5e2c-77cd-4788-b0ef-7cf0fc8a3e54&iss=https://auth1.altareq1.sandbox.apihub.openfinance.aeconst params = new URLSearchParams(window.location.search)
const code = params.get('code')!
const state = params.get('state')!
const iss = params.get('iss')!
if (state !== storedState) throw new Error('State mismatch — possible CSRF attack')
if (iss !== ISSUER) throw new Error(`Unexpected issuer: ${iss}`)from urllib.parse import urlparse, parse_qs
params = parse_qs(urlparse(callback_url).query)
code = params["code"][0]
state = params["state"][0]
iss = params["iss"][0]
if state != stored_state: raise ValueError("State mismatch — possible CSRF attack")
if iss != ISSUER: raise ValueError(f"Unexpected issuer: {iss}")See Handling Authorization Callbacks for a full guide on state validation, issuer verification, and replay prevention.
Exchanging the Code for Tokens
Step 8 - POST /token (Authorization Code)
// Token endpoint is read from .well-known/openid-configuration —
// not constructed from the issuer URL (it lives on a different host).
const TOKEN_ENDPOINT = discoveryDoc.token_endpoint
const tokenResponse = await fetch(TOKEN_ENDPOINT, {
method: 'POST',
headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
body: new URLSearchParams({
grant_type: 'authorization_code',
code,
redirect_uri: REDIRECT_URI,
code_verifier: codeVerifier, // from Step 3
client_assertion_type: 'urn:ietf:params:oauth:client-assertion-type:jwt-bearer',
client_assertion: await buildClientAssertion(),
}),
// agent: new https.Agent({ cert: transportCert, key: transportKey }),
})
const { access_token, refresh_token, expires_in } = await tokenResponse.json()# Token endpoint is read from .well-known/openid-configuration —
# not constructed from the issuer URL (it lives on a different host).
token_endpoint = discovery_doc["token_endpoint"]
token_response = httpx.post(
token_endpoint,
data={
"grant_type": "authorization_code",
"code": code,
"redirect_uri": REDIRECT_URI,
"code_verifier": code_verifier, # from Step 3
"client_assertion_type": "urn:ietf:params:oauth:client-assertion-type:jwt-bearer",
"client_assertion": build_client_assertion(),
},
# cert=("transport.crt", "transport.key"),
)
tokens = token_response.json()
access_token = tokens["access_token"]
refresh_token = tokens["refresh_token"]
expires_in = tokens["expires_in"] # 600 — access token lasts 10 minutesToken storage
Never store tokens in localStorage. Use httpOnly cookies or a server-side session store. See Tokens & Assertions for the full token lifecycle.
Initiating Payments
Encrypt PII for Payment Initiation
Each POST /payments request carries its own PersonalIdentifiableInformation — a fresh JWE encrypted for that specific payment. This follows the same JWS-inside-JWE pattern used in Step 1, but uses the Domestic Payment PII Schema Object (AEBankServiceInitiation.AEDomesticPaymentPIIProperties) rather than the consent PII schema. The creditor fields are flat on Initiation at this stage — they are not wrapped in an array.
The schema defines PersonalIdentifiableInformation for POST /payments as a oneOf with two variants:
| Variant | Form | Notes |
|---|---|---|
Domestic Payment PII Schema Object (AEDomesticPaymentPIIProperties) | object | Unencrypted form — shows the payment PII structure. For reference only. |
Encrypted PII Object (AEJWEPaymentPII) | string | Compact JWE string. MUST be used when invoking POST /payments. |
Domestic Payment PII Schema Object must be strictly followed
The object you encrypt MUST conform exactly to AEDomesticPaymentPIIProperties. Field names, nesting, and data types are validated by the LFI after decryption — any deviation will result in payment rejection. Do not add undocumented fields or omit required ones.
See Personal Identifiable Information for the complete field reference, required vs optional fields, and creditor models for each domestic payment type.
Creditor must match the consent PII
The creditor supplied here must correspond to the single beneficiary set at consent time. CreditorAccount.SchemeName, CreditorAccount.Identification, and CreditorAccount.Name must exactly match the entry in the consent PII. The LFI decrypts both PII tokens and compares them; any discrepancy results in rejection.
See Creditor for the full matching rules and field validation requirements.
Risk block is flexible per payment
Unlike the Creditor, the Risk block does not need to match the consent PII exactly. It should reflect the actual risk context of the individual payment — for example, a different Channel or updated TransactionIndicators for each payment under the consent.
Build the PII object according to the schema, then encrypt it using the same encryptPII helper from Step 1:
const paymentPii = {
Initiation: {
Creditor: [
{
Creditor: {
Name: 'Ivan England', // must match consent PII (single/multiple beneficiary)
},
CreditorAccount: {
SchemeName: 'IBAN', // must match consent PII (single/multiple beneficiary)
Identification: 'AE070331234567890123456', // must match consent PII (single/multiple beneficiary)
Name: {
en: 'Ivan David England', // must match consent PII (single/multiple beneficiary)
},
},
},
],
},
// Risk can reflect the context of this specific payment
Risk: {
PaymentContextCode: 'BillPayment',
},
}
const paymentEncryptedPII = await encryptPII(paymentPii, LFI_JWKS_URI, signingKey, SIGNING_KEY_ID)
// paymentEncryptedPII is a compact JWE string — embed it in the payment request belowpayment_pii = {
"Initiation": {
"Creditor": [
{
"Creditor": {
"Name": "Ivan England", # must match consent PII (single/multiple beneficiary)
},
"CreditorAccount": {
"SchemeName": "IBAN", # must match consent PII (single/multiple beneficiary)
"Identification": "AE070331234567890123456", # must match consent PII (single/multiple beneficiary)
"Name": {
"en": "Ivan David England", # must match consent PII (single/multiple beneficiary)
},
},
}
],
},
# Risk can reflect the context of this specific payment
"Risk": {
"PaymentContextCode": "BillPayment",
},
}
payment_encrypted_pii = encrypt_pii(payment_pii, LFI_JWKS_URI)
# payment_encrypted_pii is a compact JWE string — embed it in the payment request belowSee Personal Identifiable Information for the complete field reference, required vs optional fields, and creditor models for each domestic payment type.
See Message Encryption for details on fetching the LFI's JWKS and selecting the correct encryption key.
Step 9 - POST /payments
Include x-fapi-interaction-id and x-idempotency-key. If the customer is present at this point in the flow, also send x-fapi-customer-ip-address, x-customer-user-agent and x-fapi-auth-date if the customer has been authenticated. See Request Headers.
Submit one payment per period under this consent. The Instruction.Amount must exactly match the fixed Amount defined in PeriodicSchedule — the API Hub will reject any payment where the amount does not match, and will reject a second payment submitted within the same period.
Fields that can vary per payment
Unlike Single Instant Payment, multi-payment consents do not require PaymentPurposeCode, DebtorReference, CreditorReference, or OpenFinanceBilling to match the consent exactly. Only ConsentId must match the authorized consent. Instruction.Amount must be within the parameters the consent allows for this payment type.
import { SignJWT } from 'jose'
const LFI_API_BASE = process.env.LFI_API_BASE_URL!
async function initiateFixedPeriodicPayment(
accessToken: string,
consentId: string,
paymentEncryptedPII: string, // from the PII step above
idempotencyKey: string,
) {
// Wrapped in `message` per AEPaymentRequestSigned
const paymentPayload = {
message: {
Data: {
ConsentId: consentId, // must match the authorized consent
Instruction: {
Amount: {
Amount: '150.00', // must be within consent parameters
Currency: 'AED',
},
},
PersonalIdentifiableInformation: paymentEncryptedPII,
PaymentPurposeCode: 'ACM',
DebtorReference: 'Subscription',
CreditorReference: 'Subscription',
OpenFinanceBilling: {
Type: 'PushP2P',
},
},
},
}
// AUTHORIZATION_SERVER_ISSUER is the `issuer` value from the LFI's .well-known/openid-configuration
const signedPayment = await new SignJWT(paymentPayload)
.setProtectedHeader({ alg: 'PS256', kid: SIGNING_KEY_ID, typ: 'JWT' })
.setIssuedAt()
.setIssuer(CLIENT_ID)
.setAudience(AUTHORIZATION_SERVER_ISSUER)
.setExpirationTime('5m')
.sign(signingKey)
const paymentResponse = await fetch(`${LFI_API_BASE}/open-finance/payment/v2.1/payments`, {
method: 'POST',
headers: {
Authorization: `Bearer ${accessToken}`,
'Content-Type': 'application/jwt',
'x-idempotency-key': idempotencyKey,
'x-fapi-interaction-id': crypto.randomUUID(),
'x-fapi-auth-date': lastCustomerAuthDate,
'x-fapi-customer-ip-address': customerIpAddress,
},
body: signedPayment,
// agent: new https.Agent({ cert: transportCert, key: transportKey }),
})
const { Data: { PaymentId, Status } } = await paymentResponse.json()
return { PaymentId, Status }
}
// March payment
const { PaymentId: marPay } = await initiateFixedPeriodicPayment(access_token, consentId, paymentEncryptedPII, crypto.randomUUID())
// April payment (following month, using a refreshed access token)
const { PaymentId: aprPay } = await initiateFixedPeriodicPayment(refreshedToken, consentId, paymentEncryptedPII, crypto.randomUUID())import time
from jose import jwt as jose_jwt
def initiate_fixed_periodic_payment(
access_token: str,
consent_id: str,
payment_encrypted_pii: str, # from the PII step above
idempotency_key: str,
) -> dict:
# Wrapped in `message` per AEPaymentRequestSigned
payment_payload = {
"message": {
"Data": {
"ConsentId": consent_id, # must match the authorized consent
"Instruction": {
"Amount": {
"Amount": "150.00", # must be within consent parameters
"Currency": "AED",
}
},
"PersonalIdentifiableInformation": payment_encrypted_pii,
"PaymentPurposeCode": "ACM",
"DebtorReference": "Subscription",
"CreditorReference": "Subscription",
"OpenFinanceBilling": {
"Type": "PushP2P",
},
}
}
}
# AUTHORIZATION_SERVER_ISSUER is the `issuer` value from the LFI's .well-known/openid-configuration
now = int(time.time())
signed_payment = jose_jwt.encode(
{
**payment_payload,
"iss": CLIENT_ID,
"aud": AUTHORIZATION_SERVER_ISSUER,
"iat": now,
"exp": now + 300,
},
signing_key,
algorithm="PS256",
headers={"kid": SIGNING_KEY_ID, "typ": "JWT"},
)
response = httpx.post(
f"{LFI_API_BASE}/open-finance/payment/v2.1/payments",
headers={
"Authorization": f"Bearer {access_token}",
"Content-Type": "application/jwt",
"x-idempotency-key": idempotency_key,
"x-fapi-interaction-id": str(uuid.uuid4()),
"x-fapi-auth-date": last_customer_auth_date,
"x-fapi-customer-ip-address": customer_ip_address,
},
content=signed_payment,
# cert=("transport.crt", "transport.key"),
)
data = response.json()["Data"]
return {"payment_id": data["PaymentId"], "status": data["Status"]}
# March payment
mar_pay = initiate_fixed_periodic_payment(access_token, consent_id, payment_encrypted_pii, str(uuid.uuid4()))
# April payment (following month, using a refreshed access token)
apr_pay = initiate_fixed_periodic_payment(refreshed_token, consent_id, payment_encrypted_pii, str(uuid.uuid4()))Fixed amount and period enforcement
The API Hub will reject a payment if Instruction.Amount does not exactly match PeriodicSchedule.Amount, if a payment has already been submitted in the current period, or if any lifetime cumulative cap has been reached.
Token refresh for subsequent payments
The initial access token expires after 10 minutes. For subsequent on-demand payments, use the refresh_token to obtain a new access token without re-involving the user:
// Token endpoint is read from .well-known/openid-configuration —
// not constructed from the issuer URL (it lives on a different host).
const TOKEN_ENDPOINT = discoveryDoc.token_endpoint
const refreshResponse = await fetch(TOKEN_ENDPOINT, {
method: 'POST',
headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
body: new URLSearchParams({
grant_type: 'refresh_token',
refresh_token: storedRefreshToken,
client_assertion_type: 'urn:ietf:params:oauth:client-assertion-type:jwt-bearer',
client_assertion: await buildClientAssertion(),
}),
// agent: new https.Agent({ cert: transportCert, key: transportKey }),
})
const { access_token: newToken, refresh_token: newRefresh } = await refreshResponse.json()
// Update your stored tokens# Token endpoint is read from .well-known/openid-configuration —
# not constructed from the issuer URL (it lives on a different host).
token_endpoint = discovery_doc["token_endpoint"]
refresh_response = httpx.post(
token_endpoint,
data={
"grant_type": "refresh_token",
"refresh_token": stored_refresh_token,
"client_assertion_type": "urn:ietf:params:oauth:client-assertion-type:jwt-bearer",
"client_assertion": build_client_assertion(),
},
# cert=("transport.crt", "transport.key"),
)
tokens = refresh_response.json()
access_token = tokens["access_token"]
refresh_token = tokens["refresh_token"]
# Update your stored tokensSee Tokens & Assertions for refresh token lifetimes and rotation policy.
A successful POST /payments
A 201 Created response is returned as a signed JWT (application/jwt). Verify the signature using the LFI's public signing key before reading the payload.
Response headers
| Header | Description |
|---|---|
Location | URL of the created payment resource — /open-finance/payment/v2.1/payments/{PaymentId} |
x-fapi-interaction-id | Echo of the interaction ID from the request |
x-idempotency-key | Echo of the idempotency key from the request |
Response body — Data
| Field | Required | Description |
|---|---|---|
PaymentId | Yes | LFI-assigned unique identifier for this payment resource (use this to poll for status) |
ConsentId | Yes | The consent this payment is bound to |
Status | Yes | Current payment status — see status lifecycle below |
StatusUpdateDateTime | Yes | ISO 8601 datetime of the last status change |
CreationDateTime | Yes | ISO 8601 datetime when the payment resource was created |
Instruction.Amount | Yes | Echoes back the amount and currency from the request |
PaymentPurposeCode | Yes | Echoes back the payment purpose code |
OpenFinanceBilling | Yes | Echoes back the billing parameters |
PaymentTransactionId | No | End-to-end transaction ID generated by the Aani payment rails once the payment is submitted for settlement. Not present at Pending. |
DebtorReference | No | Echoes back the debtor reference if provided |
RejectReasonCode | No | Array of { Code, Message } objects — present only when Status is Rejected |
Status lifecycle
| Status | Description |
|---|---|
Pending | The payment has been accepted by the LFI and queued for processing. This is the typical status immediately after creation. |
AcceptedSettlementCompleted | The debtor's account has been debited. |
AcceptedWithoutPosting | The receiving LFI has accepted the payment but has not yet credited the creditor account. |
AcceptedCreditSettlementCompleted | The creditor account has been credited. Payment is fully settled. |
Rejected | The payment was rejected. Inspect RejectReasonCode for the reason. |
Links
| Field | Description |
|---|---|
Self | URL to this payment resource — use for status polling |
Related | URL to the associated consent — /open-finance/v2.1/payment-consents/{ConsentId} |
Example response payload
The payload is the verified body of the signed JWT. Per AEPaymentIdResponseSigned, Data and Links are wrapped in a message envelope.
{
"message": {
"Data": {
"PaymentId": "83b47199-90c2-4c05-9ef1-aeae68b0fc7c",
"ConsentId": "b8f42378-10ac-46a1-8d20-4e020484216d",
"Status": "Pending",
"StatusUpdateDateTime": "2026-05-03T15:46:01+00:00",
"CreationDateTime": "2026-05-03T15:46:01+00:00",
"Instruction": {
"Amount": {
"Amount": "100.00",
"Currency": "AED"
}
},
"PaymentPurposeCode": "ACM",
"DebtorReference": "Invoice 1234",
"OpenFinanceBilling": {
"Type": "PushP2P"
}
},
"Links": {
"Self": "https://api.lfi.example/open-finance/payment/v2.1/payments/83b47199-90c2-4c05-9ef1-aeae68b0fc7c",
"Related": "https://api.lfi.example/open-finance/v2.1/payment-consents/b8f42378-10ac-46a1-8d20-4e020484216d"
}
}
}Store the PaymentId
Persist PaymentId immediately — it is required to poll GET /payments/{PaymentId} for status updates. A payment typically moves from Pending to a terminal status within seconds, but network conditions may require polling.
See the POST /payments API reference for the full request and response schema.
Consent stays Authorized
After each successful payment, the consent remains in the Authorized state until the next period begins (unless lifetime cumulative caps are reached or the consent expires). You do not need to re-initiate the authorization flow.
