BillKit/Docs Console
Specification

OpenAPI spec

2026-09-13 167 operations · 528 KB

openapi.json

Bundled, all $refs resolved against components. Recommended for codegen.

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Browse operations

The explorer lists the 90 operations an API key can reach. The rest of the 167 in the document authenticate with a console session or a billing-portal token: they are published so the spec describes the whole service, but they are not part of the developer surface and nothing you build should call them.

90 / 90 operations

Customers

People and organisations you bill. 7
GET /v1/customers List Customers

List your customers, newest first. Requires a secret or restricted key with customers:read.

GET /v1/customers 
curl -X GET https://api.billkit.eu/v1/customers \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/customers Create Customer

Create a customer, the record everything else in an account hangs off. Requires a secret or restricted key with customers:write.

POST /v1/customers 
curl -X POST https://api.billkit.eu/v1/customers \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
DELETE /v1/customers/{customer_id} Delete Customer

Delete a customer. Requires a secret or restricted key with customers:write.

DELETE /v1/customers/{customer_id} 
curl -X DELETE https://api.billkit.eu/v1/customers/cus_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/customers/{customer_id} Get Customer

Retrieve one customer. Requires a secret or restricted key with customers:read.

GET /v1/customers/{customer_id} 
curl -X GET https://api.billkit.eu/v1/customers/cus_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/customers/{customer_id} Update Customer

Update a customer's details. Requires a secret or restricted key with customers:write.

POST /v1/customers/{customer_id} 
curl -X POST https://api.billkit.eu/v1/customers/cus_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
POST /v1/customers/{customer_id}/purge Purge Customer

Erase a customer's personal data while keeping their financial history. Requires a secret or restricted key with customers:write.

POST /v1/customers/{customer_id}/purge 
curl -X POST https://api.billkit.eu/v1/customers/cus_9XKp2vQ1/purge \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
POST /v1/customers/{customer_id}/vat_number Set Customer Vat Number

Record a business customer's VAT registration number and check it. Requires a secret or restricted key with customers:write.

POST /v1/customers/{customer_id}/vat_number 
curl -X POST https://api.billkit.eu/v1/customers/cus_9XKp2vQ1/vat_number \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →

Products

The things you sell, independent of what they cost. 4
GET /v1/products List Products

List your products, newest first. Requires a secret or restricted key with products:read.

GET /v1/products 
curl -X GET https://api.billkit.eu/v1/products \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/products Create Product

Create a product, the thing you sell. Requires a secret or restricted key with products:write.

POST /v1/products 
curl -X POST https://api.billkit.eu/v1/products \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name":"Ada Lovelace"}'
Full reference for this operation →
GET /v1/products/{product_id} Get Product

Retrieve one product. Requires a secret or restricted key with products:read.

GET /v1/products/{product_id} 
curl -X GET https://api.billkit.eu/v1/products/prod_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/products/{product_id} Update Product

Update a product's details, or archive it. Requires a secret or restricted key with products:write.

POST /v1/products/{product_id} 
curl -X POST https://api.billkit.eu/v1/products/prod_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →

Prices

Amount, currency, interval and tax behaviour for a product. 4
GET /v1/prices List Prices

List your prices, newest first. Requires a secret or restricted key with prices:read.

GET /v1/prices 
curl -X GET https://api.billkit.eu/v1/prices \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/prices Create Price

Create a price, which is what a customer actually buys. Requires a secret or restricted key with prices:write.

POST /v1/prices 
curl -X POST https://api.billkit.eu/v1/prices \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"interval":"month","product_id":"prod_9XKp2vQ1"}'
Full reference for this operation →
GET /v1/prices/{price_id} Get Price

Retrieve one price, including its trial, tax and refund-window settings. Requires a secret or restricted key with prices:read.

GET /v1/prices/{price_id} 
curl -X GET https://api.billkit.eu/v1/prices/price_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/prices/{price_id} Update Price

Archive a price so it stops selling, or put it back on sale. Requires a secret or restricted key with prices:write.

POST /v1/prices/{price_id} 
curl -X POST https://api.billkit.eu/v1/prices/price_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →

Subscriptions

Recurring agreements between a customer and a price. 9
GET /v1/subscriptions List Subscriptions

List subscriptions, newest first. Requires a secret or restricted key with subscriptions:read.

GET /v1/subscriptions 
curl -X GET https://api.billkit.eu/v1/subscriptions \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/subscriptions/{subscription_id} Get Subscription

Retrieve one subscription. Requires a secret or restricted key with subscriptions:read.

GET /v1/subscriptions/{subscription_id} 
curl -X GET https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/cancel Cancel Subscription

Stop a subscription renewing at the end of the current period. Requires a secret or restricted key with subscriptions:cancel.

POST /v1/subscriptions/{subscription_id}/cancel 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/cancel \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/pause Pause Subscription

Stop a subscription renewing, without ending it. Requires a secret or restricted key with subscriptions:write.

POST /v1/subscriptions/{subscription_id}/pause 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/pause \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/preview_update Preview Update Subscription

Quote what moving this subscription to another price would cost. Requires a secret or restricted key with subscriptions:read.

POST /v1/subscriptions/{subscription_id}/preview_update 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/preview_update \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"target_price_id":"price_9XKp2vQ1"}'
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/reactivate Reactivate Subscription

Undo a pending cancellation and keep the subscription renewing. Requires a secret or restricted key with subscriptions:write.

POST /v1/subscriptions/{subscription_id}/reactivate 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/reactivate \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/reauthorize_payment_method Reauthorize Payment Method

Start the flow for a customer to replace their payment method. Requires a secret or restricted key with subscriptions:write.

POST /v1/subscriptions/{subscription_id}/reauthorize_payment_method 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/reauthorize_payment_method \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"return_url":"https://acme.example/welcome"}'
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/resume Resume Subscription

Restart renewals on a paused subscription. Requires a secret or restricted key with subscriptions:write.

POST /v1/subscriptions/{subscription_id}/resume 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/resume \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/update Update Subscription

Move a subscription to a different price, charging the difference now. Requires a secret or restricted key with subscriptions:write.

POST /v1/subscriptions/{subscription_id}/update 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/update \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"target_price_id":"price_9XKp2vQ1"}'
Full reference for this operation →

Checkout

Hosted and embedded payment sessions, and saved payment methods. 4
POST /v1/checkout/one_shot Create One Shot

Charge a customer once, with no subscription and no stored mandate. Requires a secret or restricted key with checkout_sessions:write.

POST /v1/checkout/one_shot 
curl -X POST https://api.billkit.eu/v1/checkout/one_shot \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"amount_cents":1900,"currency":"EUR","customer_id":"cus_9XKp2vQ1","method":"creditcard","success_url":"https://acme.example/welcome"}'
Full reference for this operation →
GET /v1/checkout/one_shot/{one_shot_id} Get One Shot

Retrieve one one-off payment, including how much of it has been refunded. Requires a secret or restricted key with checkout_sessions:read.

GET /v1/checkout/one_shot/{one_shot_id} 
curl -X GET https://api.billkit.eu/v1/checkout/one_shot/osp_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/checkout/sessions Create Checkout Session

Start a subscription sign-up. Requires a secret or restricted key with checkout_sessions:write.

POST /v1/checkout/sessions 
curl -X POST https://api.billkit.eu/v1/checkout/sessions \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"cancel_url":"https://acme.example/welcome","price_id":"price_9XKp2vQ1","success_url":"https://acme.example/welcome"}'
Full reference for this operation →
GET /v1/checkout/sessions/{checkout_id} Get Checkout Session

Retrieve one checkout session, to see whether the customer completed it. Requires a secret or restricted key with checkout_sessions:read.

GET /v1/checkout/sessions/{checkout_id} 
curl -X GET https://api.billkit.eu/v1/checkout/sessions/cs_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Usage records

Metered events reported against a subscription. 3
GET /v1/subscriptions/{subscription_id}/usage_records List Usage Records

List the usage reported against one metered subscription. Requires a secret or restricted key with usage_records:read.

GET /v1/subscriptions/{subscription_id}/usage_records 
curl -X GET https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/usage_records \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/subscriptions/{subscription_id}/usage_records Create Usage Record

Report usage against a metered subscription. Requires a secret or restricted key with usage_records:write.

POST /v1/subscriptions/{subscription_id}/usage_records 
curl -X POST https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/usage_records \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"quantity":0}'
Full reference for this operation →
GET /v1/subscriptions/{subscription_id}/usage_summary Get Usage Summary

See what the next period close will bill, before it bills it. Requires a secret or restricted key with usage_records:read.

GET /v1/subscriptions/{subscription_id}/usage_summary 
curl -X GET https://api.billkit.eu/v1/subscriptions/sub_9XKp2vQ1/usage_summary \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Invoices

Statements generated at the end of a billing period. 5
GET /v1/invoices List Invoices

List invoices, newest first. Requires a secret or restricted key with invoices:read.

GET /v1/invoices 
curl -X GET https://api.billkit.eu/v1/invoices \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/invoices/{invoice_id} Get Invoice

Retrieve one invoice, with its line items. Requires a secret or restricted key with invoices:read.

GET /v1/invoices/{invoice_id} 
curl -X GET https://api.billkit.eu/v1/invoices/inv_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/invoices/{invoice_id}/email Email Invoice

Send the customer their invoice again. Requires a secret or restricted key with invoices:write.

POST /v1/invoices/{invoice_id}/email 
curl -X POST https://api.billkit.eu/v1/invoices/inv_9XKp2vQ1/email \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/invoices/{invoice_id}/pdf Get Invoice Pdf

Download the invoice as a PDF. Requires a secret or restricted key with invoices:read.

GET /v1/invoices/{invoice_id}/pdf 
curl -X GET https://api.billkit.eu/v1/invoices/inv_9XKp2vQ1/pdf \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/invoices/{invoice_id}/void Void Invoice Route

Void an invoice, stating that the sale was never owed. Requires a secret or restricted key with invoices:write.

POST /v1/invoices/{invoice_id}/void 
curl -X POST https://api.billkit.eu/v1/invoices/inv_9XKp2vQ1/void \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →

Credit notes

Reversals issued against an invoice. 3
GET /v1/credit_notes List Credit Notes

List credit notes, newest first. Requires a secret or restricted key with credit_notes:read.

GET /v1/credit_notes 
curl -X GET https://api.billkit.eu/v1/credit_notes \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/credit_notes/{credit_note_id} Get Credit Note

Retrieve one credit note. Requires a secret or restricted key with credit_notes:read.

GET /v1/credit_notes/{credit_note_id} 
curl -X GET https://api.billkit.eu/v1/credit_notes/cn_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/credit_notes/{credit_note_id}/pdf Get Credit Note Pdf

Download the credit note as a PDF. Requires a secret or restricted key with credit_notes:read.

GET /v1/credit_notes/{credit_note_id}/pdf 
curl -X GET https://api.billkit.eu/v1/credit_notes/cn_9XKp2vQ1/pdf \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Payments

Individual charge attempts and their outcome. 3
GET /v1/payments List Payments

List subscription payments, newest first. Requires a secret or restricted key with payments:read.

GET /v1/payments 
curl -X GET https://api.billkit.eu/v1/payments \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/payments/{payment_id} Get Payment

Retrieve one subscription payment, including how much has been refunded. Requires a secret or restricted key with payments:read.

GET /v1/payments/{payment_id} 
curl -X GET https://api.billkit.eu/v1/payments/pay_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/payments/{payment_id}/provider Get Payment Provider Payload

Fetch the provider's own record of this charge, live. Requires a secret or restricted key with payments:read.

GET /v1/payments/{payment_id}/provider 
curl -X GET https://api.billkit.eu/v1/payments/pay_9XKp2vQ1/provider \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Refunds

Full and partial returns against a settled payment. 3
GET /v1/refunds List Refunds

List refunds, newest first. Requires a secret or restricted key with refunds:read.

GET /v1/refunds 
curl -X GET https://api.billkit.eu/v1/refunds \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/refunds Create Refund

Refund a payment, in full or in part. Requires a secret or restricted key with refunds:write.

POST /v1/refunds 
curl -X POST https://api.billkit.eu/v1/refunds \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
GET /v1/refunds/{refund_id} Get Refund

Retrieve one refund and check whether it has settled. Requires a secret or restricted key with refunds:read.

GET /v1/refunds/{refund_id} 
curl -X GET https://api.billkit.eu/v1/refunds/re_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Disputes

Chargebacks raised by the cardholder or their bank. 2
GET /v1/disputes List Disputes

List chargebacks raised against your payments, newest first. Requires a secret or restricted key with disputes:read.

GET /v1/disputes 
curl -X GET https://api.billkit.eu/v1/disputes \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/disputes/{dispute_id} Get Dispute

Retrieve one chargeback. Requires a secret or restricted key with disputes:read.

GET /v1/disputes/{dispute_id} 
curl -X GET https://api.billkit.eu/v1/disputes/dp_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Coupons

Percentage and fixed-amount discounts applied at checkout. 5
GET /v1/coupons List Coupons

List coupons, newest first. Requires a secret or restricted key with coupons:read.

GET /v1/coupons 
curl -X GET https://api.billkit.eu/v1/coupons \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/coupons Create Coupon

Create a discount code customers can enter at checkout. Requires a secret or restricted key with coupons:write.

POST /v1/coupons 
curl -X POST https://api.billkit.eu/v1/coupons \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"code":"string","discount_type":"percent","discount_value":0}'
Full reference for this operation →
GET /v1/coupons/{coupon_id} Get Coupon

Retrieve one coupon, including how many times it has been redeemed. Requires a secret or restricted key with coupons:read.

GET /v1/coupons/{coupon_id} 
curl -X GET https://api.billkit.eu/v1/coupons/coup_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/coupons/{coupon_id} Update Coupon

Update a coupon's limits, or withdraw it. Requires a secret or restricted key with coupons:write.

POST /v1/coupons/{coupon_id} 
curl -X POST https://api.billkit.eu/v1/coupons/coup_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
POST /v1/coupons/validate Validate Coupon

Check whether a code is usable, and what it would take off. Requires a secret or restricted key with coupons:read.

POST /v1/coupons/validate 
curl -X POST https://api.billkit.eu/v1/coupons/validate \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"code":"string"}'
Full reference for this operation →

Tax rates

VAT and sales-tax rates applied to a line item. 4
GET /v1/tax_rates List Tax Rates

List tax rates, newest first. Requires a secret or restricted key with tax_rates:read.

GET /v1/tax_rates 
curl -X GET https://api.billkit.eu/v1/tax_rates \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/tax_rates Create Tax Rate

Set the VAT rate to charge customers in one country. Requires a secret or restricted key with tax_rates:write.

POST /v1/tax_rates 
curl -X POST https://api.billkit.eu/v1/tax_rates \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"country_code":"NL","rate_basis_points":0}'
Full reference for this operation →
GET /v1/tax_rates/{tax_rate_id} Get Tax Rate

Retrieve one tax rate. Requires a secret or restricted key with tax_rates:read.

GET /v1/tax_rates/{tax_rate_id} 
curl -X GET https://api.billkit.eu/v1/tax_rates/tr_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/tax_rates/{tax_rate_id} Update Tax Rate

Correct a tax rate, retire it, or bring a retired one back into use. Requires a secret or restricted key with tax_rates:write.

POST /v1/tax_rates/{tax_rate_id} 
curl -X POST https://api.billkit.eu/v1/tax_rates/tr_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →

Webhook endpoints

Endpoint registration, signing secrets and delivery attempts. 10
GET /v1/webhook_endpoints List Webhook Endpoints

List your webhook endpoints, newest first. Requires a secret or restricted key with webhook_endpoints:read.

GET /v1/webhook_endpoints 
curl -X GET https://api.billkit.eu/v1/webhook_endpoints \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/webhook_endpoints Create Webhook Endpoint

Register a URL to receive events. Requires a secret or restricted key with webhook_endpoints:write.

POST /v1/webhook_endpoints 
curl -X POST https://api.billkit.eu/v1/webhook_endpoints \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://acme.example/welcome"}'
Full reference for this operation →
DELETE /v1/webhook_endpoints/{endpoint_id} Delete Webhook Endpoint

Delete a webhook endpoint. Requires a secret or restricted key with webhook_endpoints:write.

DELETE /v1/webhook_endpoints/{endpoint_id} 
curl -X DELETE https://api.billkit.eu/v1/webhook_endpoints/we_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/webhook_endpoints/{endpoint_id} Get Webhook Endpoint

Retrieve one webhook endpoint's configuration. Requires a secret or restricted key with webhook_endpoints:read.

GET /v1/webhook_endpoints/{endpoint_id} 
curl -X GET https://api.billkit.eu/v1/webhook_endpoints/we_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/webhook_endpoints/{endpoint_id} Update Webhook Endpoint

Update a webhook endpoint's URL, event list, description or status. Requires a secret or restricted key with webhook_endpoints:write.

POST /v1/webhook_endpoints/{endpoint_id} 
curl -X POST https://api.billkit.eu/v1/webhook_endpoints/we_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
GET /v1/webhook_endpoints/{endpoint_id}/deliveries List Webhook Endpoint Deliveries

List the delivery attempts made to one webhook endpoint, newest first. Requires a secret or restricted key with webhook_endpoints:read.

GET /v1/webhook_endpoints/{endpoint_id}/deliveries 
curl -X GET https://api.billkit.eu/v1/webhook_endpoints/we_9XKp2vQ1/deliveries \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/webhook_endpoints/{endpoint_id}/deliveries/{delivery_id} Get Webhook Delivery

Retrieve one delivery attempt. Requires a secret or restricted key with webhook_endpoints:read.

GET /v1/webhook_endpoints/{endpoint_id}/deliveries/{delivery_id} 
curl -X GET https://api.billkit.eu/v1/webhook_endpoints/we_9XKp2vQ1/deliveries/whd_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/webhook_endpoints/{endpoint_id}/deliveries/{delivery_id}/redeliver Redeliver Webhook Delivery

Send one delivery again, straight away. Requires a secret or restricted key with webhook_endpoints:write.

POST /v1/webhook_endpoints/{endpoint_id}/deliveries/{delivery_id}/redeliver 
curl -X POST https://api.billkit.eu/v1/webhook_endpoints/we_9XKp2vQ1/deliveries/whd_9XKp2vQ1/redeliver \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/webhook_endpoints/{endpoint_id}/rotate_secret Rotate Webhook Endpoint Secret

Replace the endpoint's signing secret. Requires a secret or restricted key with webhook_endpoints:write.

POST /v1/webhook_endpoints/{endpoint_id}/rotate_secret 
curl -X POST https://api.billkit.eu/v1/webhook_endpoints/we_9XKp2vQ1/rotate_secret \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/webhook_endpoints/event_types List Event Types

Every event type this deployment can deliver. Requires a secret or restricted key with webhook_endpoints:read.

GET /v1/webhook_endpoints/event_types 
curl -X GET https://api.billkit.eu/v1/webhook_endpoints/event_types \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Events

The immutable log every webhook is delivered from. 3
GET /v1/events List Events

List the events recorded for your account, newest first. Requires a secret or restricted key with events:read.

GET /v1/events 
curl -X GET https://api.billkit.eu/v1/events \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/events/{event_id} Get Event

Retrieve one event, including the full data payload it carried. Requires a secret or restricted key with events:read.

GET /v1/events/{event_id} 
curl -X GET https://api.billkit.eu/v1/events/evt_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/events/stream Stream Events

Hold a connection open and receive this account's events as they happen. Requires a secret or restricted key with events:read.

GET /v1/events/stream 
curl -X GET https://api.billkit.eu/v1/events/stream \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Metrics

Aggregate revenue and subscription counts for a dashboard. 1
GET /v1/metrics/home Get Home Metrics

Four headline numbers for your account, in one call. Requires a secret or restricted key with metrics:read.

GET /v1/metrics/home 
curl -X GET https://api.billkit.eu/v1/metrics/home \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

API keys

Mint, scope and revoke the keys that reach this API. 4
GET /v1/api_keys List Api Keys

List your API keys, newest first. Requires a secret or restricted key with api_keys:read.

GET /v1/api_keys 
curl -X GET https://api.billkit.eu/v1/api_keys \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/api_keys Create Api Key

Issue a new API key. Requires a secret or restricted key with api_keys:write.

POST /v1/api_keys 
curl -X POST https://api.billkit.eu/v1/api_keys \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
GET /v1/api_keys/{api_key_id} Get Api Key

Retrieve one API key's metadata. Requires a secret or restricted key with api_keys:read.

GET /v1/api_keys/{api_key_id} 
curl -X GET https://api.billkit.eu/v1/api_keys/ak_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/api_keys/{api_key_id}/revoke Revoke Api Key

Revoke an API key so it stops working. Requires a secret or restricted key with api_keys:write.

POST /v1/api_keys/{api_key_id}/revoke 
curl -X POST https://api.billkit.eu/v1/api_keys/ak_9XKp2vQ1/revoke \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Audit logs

Who changed what, from the console or the API. 2
GET /v1/audit_logs List Audit Logs

List the record of who changed what in your account, newest first. Requires a secret or restricted key with audit_logs:read.

GET /v1/audit_logs 
curl -X GET https://api.billkit.eu/v1/audit_logs \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/audit_logs/{audit_log_id} Get Audit Log

Retrieve one audit entry, including the details recorded with it. Requires a secret or restricted key with audit_logs:read.

GET /v1/audit_logs/{audit_log_id} 
curl -X GET https://api.billkit.eu/v1/audit_logs/4b2a1e90-7c3d-4f18-9a55-1c0b6de3a742 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Tenant

Your account settings, branding and data export. 7
GET /v1/tenant/billing_profile Get Billing Profile

Read your own registered country and VAT number. Requires a secret or restricted key with tenant:read.

GET /v1/tenant/billing_profile 
curl -X GET https://api.billkit.eu/v1/tenant/billing_profile \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/tenant/billing_profile Update Billing Profile

Set your registered country, and optionally your own VAT number. Requires a secret or restricted key with tenant:write.

POST /v1/tenant/billing_profile 
curl -X POST https://api.billkit.eu/v1/tenant/billing_profile \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"country_code":"NL"}'
Full reference for this operation →
GET /v1/tenant/capabilities Get Tenant Capabilities

Read which payment methods and currencies your account can actually use. Requires a secret or restricted key with tenant:read.

GET /v1/tenant/capabilities 
curl -X GET https://api.billkit.eu/v1/tenant/capabilities \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/tenant/export Export Tenant Data

Download everything in your account as one JSON file. Requires a secret or restricted key with data:export.

GET /v1/tenant/export 
curl -X GET https://api.billkit.eu/v1/tenant/export \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/tenant/portal_branding Get Portal Branding

Read how your billing portal is branded. Requires a secret or restricted key with tenant:read.

GET /v1/tenant/portal_branding 
curl -X GET https://api.billkit.eu/v1/tenant/portal_branding \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/tenant/portal_branding Update Portal Branding

Set the business name, logo, support email and colours your customers see in the billing portal. Requires a secret or restricted key with tenant:write.

POST /v1/tenant/portal_branding 
curl -X POST https://api.billkit.eu/v1/tenant/portal_branding \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{}'
Full reference for this operation →
POST /v1/tenant/provider_credential Rotate Tenant Provider Credential

Replace the payment provider API key BillKit uses to charge on your behalf. Requires a secret or restricted key with tenant:write.

POST /v1/tenant/provider_credential 
curl -X POST https://api.billkit.eu/v1/tenant/provider_credential \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"api_key":"string"}'
Full reference for this operation →

Test clocks

Advance time in test mode to exercise a year of billing in a minute. 5
GET /v1/test_clocks List Test Clocks

List your test clocks, newest first. Test mode only. Requires a secret or restricted key with test_clocks:read.

GET /v1/test_clocks 
curl -X GET https://api.billkit.eu/v1/test_clocks \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/test_clocks Create Test Clock

Create a frozen clock so you can test billing over time. Requires a secret or restricted key with test_clocks:write.

POST /v1/test_clocks 
curl -X POST https://api.billkit.eu/v1/test_clocks \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"frozen_time":1789392000}'
Full reference for this operation →
DELETE /v1/test_clocks/{test_clock_id} Delete Test Clock

Delete a test clock. Requires a secret or restricted key with test_clocks:write.

DELETE /v1/test_clocks/{test_clock_id} 
curl -X DELETE https://api.billkit.eu/v1/test_clocks/tc_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
GET /v1/test_clocks/{test_clock_id} Get Test Clock

Retrieve one test clock and the time it is currently frozen at. Requires a secret or restricted key with test_clocks:read.

GET /v1/test_clocks/{test_clock_id} 
curl -X GET https://api.billkit.eu/v1/test_clocks/tc_9XKp2vQ1 \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →
POST /v1/test_clocks/{test_clock_id}/advance Advance Test Clock

Move a test clock forward and let everything due in between happen. Requires a secret or restricted key with test_clocks:write.

POST /v1/test_clocks/{test_clock_id}/advance 
curl -X POST https://api.billkit.eu/v1/test_clocks/tc_9XKp2vQ1/advance \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"frozen_time":1789392000}'
Full reference for this operation →

Billing portal

Server-side entry points for the customer-facing portal. 2
POST /v1/billing_portal/sessions Create Portal Session

Mint a link that lets a customer manage their own subscription. Requires a secret or restricted key with subscriptions:write.

POST /v1/billing_portal/sessions 
curl -X POST https://api.billkit.eu/v1/billing_portal/sessions \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"return_url":"https://acme.example/welcome","subscription_id":"sub_9XKp2vQ1"}'
Full reference for this operation →
POST /v1/billing_portal/sessions/{session_id}/revoke Revoke Portal Session

Invalidate a portal link that is already out in the world. Requires a secret or restricted key with subscriptions:write.

POST /v1/billing_portal/sessions/{session_id}/revoke 
curl -X POST https://api.billkit.eu/v1/billing_portal/sessions/bps_9XKp2vQ1/revoke \
  -H "Authorization: Bearer $BILLKIT_SECRET_KEY"
Full reference for this operation →

Generate a client

Point any OpenAPI generator at the spec URL above. Regenerate when you want newly added fields; releases add optional fields rather than changing existing ones.

shell 
npx @openapitools/openapi-generator-cli generate \
  -i https://api.billkit.eu/openapi.json \
  -g java -o ./billkit-java

Spec changelog

Version Change
2026-09-13 First published.