Creating a payment
Send the amount, description and order contents — you get back a payment ID and a checkout link.
Online payment integration
Payment API for accepting online payments
Create payments from your own backend, receive statuses via webhooks, issue refunds and fiscal receipts. MulenPay gives you the infrastructure to accept payments on your website, in your app and in your CRM.
Capabilities
What you can do with the payment API
The full lifecycle of a transaction — from creating a payment to refunds and receipts
Retrieving a payment
Request a payment by its ID and see the status, amount, payment method and date.
Linking to the order
Pass your own order number, customer details and how long the checkout link stays valid.
Refunding a transaction
A single request with the payment ID refunds the transaction in full.
Receipts for a payment
Retrieve the fiscal receipts for a specific transaction together with the payment data.
Listing and export
Filter payments by date, status, amount and payment method, and export the register to XLSX.
Fiscal receipts are generated through the Ukassa and Webkassa online cash registers. MulenPay provides software and infrastructure solutions. The service does not offer financial, payment, banking or investment services in its own name: all financial operations are carried out by licensed providers and partners.
Who it's for
Which projects the MulenPay API suits
When payment has to live inside your own product
Online stores
The cart creates a payment through an API request, and the order status in your CMS updates without manual reconciliation.
SaaS and online services
The customer pays for a plan inside their account and gets access to the features straight away.
Marketplaces and aggregators
Hundreds of sellers and orders — the API ties every payment to a specific deal and seller.
Online schools
The platform receives payment confirmation and unlocks the course for the student automatically.
Mobile apps
Your app backend creates the payment and hands the user a ready-made checkout link.
CRM and internal systems
A manager issues an invoice from the interface they already use, without switching to a separate dashboard.
The flow
How a payment goes through the API
Five steps from a request on your server to settlement under the contract
1. Your server creates a payment via the API
Your server sends the amount and order description, and gets a checkout link back in the response.
2. The customer pays for the order
The customer opens the link, chooses a card or SBP and confirms the payment.
3. MulenPay sends a webhook
A server-side notification with the final payment status arrives at the address you specified.
4. Your site updates the order status
Your system accepts the notification, marks the order as paid and triggers fulfilment.
5. Funds are settled under the contract
Settlements are handled by licensed providers and partners; the procedure and timelines are set out in the contract.
Start integrating
A payment API and a clear start
Leave a request — we'll issue your keys, answer your questions about the methods and help you run your first test payment.
Notifications
Webhooks and payment statuses
Your system learns about a payment from the server, not from the customer's browser
Notification endpoint
In your shop settings you specify the address and the events you want webhooks for.
Payment lifecycle
A payment moves through the statuses: created, processing, processed, cancelled, error, hold and provider hold.
Resending a notification
If your server was unavailable, you trigger the resend yourself — from the dashboard or with a request.
Checking on demand
Confirm the status with a direct request for the payment: the success page is not proof of payment.
Webhook statistics
Review the response codes returned by your server over a period and export the statistics to CSV.
Idempotency, event deduplication and processing logs are covered in our technical article — link at the bottom of the page.
After the payment
Refunds and cancellations
Issue a refund with a request from your own system or manually in the dashboard
Refunds via API
Send a request with the payment ID and the transaction is refunded to the customer in full.
Full amount only
There are no partial refunds via the API: the refund request does not take an amount.
Cancellation before payment
An unpaid payment moves to the cancelled status — for example, once the checkout link expires.
Refunds from the dashboard
A manager can perform the same operation by hand — no developer involvement needed.
When a refund isn't available
If a transaction cannot be refunded, the API returns an error and the payment status stays unchanged.
MulenPay provides software and infrastructure solutions. The service does not offer financial, payment, banking or investment services in its own name: all financial operations are carried out by licensed providers and partners, and the refund procedure and timelines are set out in the contract.
For developers
Test environment and documentation
Run through the payment flow before real traffic reaches your site
Demo payment
A demo payment is available on the site: walk through the whole flow and see how the form behaves.
Documentation
Methods, request parameters and response formats are all documented at docs.mulenpay.com.
Request examples
Ready-made examples for creating a payment, checking a status and issuing a refund drop straight into your code.
Testing the scenarios
Before launch, test a successful payment, a decline, a repeated notification and a refund.
Security
API security
Data, access and notifications are protected at the infrastructure level
Payment data protection
Payment data is processed in an environment certified to PCI DSS Level 1 v4.0.
Shop key
You issue your API access key in the dashboard and can reissue it at any time.
Request transport
API requests are authorised with your shop key and transmitted over a secure HTTPS connection.
Roles and access
Give your developer access to the API settings while the financial sections of the dashboard stay closed.
Questions and answers
Frequently asked questions
What developers ask before they start integrating
You need the API when payment has to be embedded in your own website, app, CRM or customer account: you create a payment with your own order data, get a checkout link, check the status, issue refunds and request fiscal receipts — all from your own system. The widget and payment links solve the same task without code, but offer less flexibility: a marketer or manager sets them up and the scenario stays fixed.
Further reading
Articles on integration and accepting payments
How to integrate a payment API and handle statuses reliably
Idempotency, event deduplication, lost webhooks and the order processing log.
How internet acquiring works: the payment flow, statuses and refunds
What happens to a payment after the customer presses Pay, and which statuses your backend sees along the way.
Why payment gateway and checkout widget errors happen
Where declines come from, what to show the customer and what to do when the status is unknown.
How to set up payment acceptance in an online store
Connecting cart, order and payment: what to prepare before your first real transaction.
Ready to connect the payment API?
Leave a request — we'll issue your keys and help you test the integration before launch.
Telegram bot
@Mulenpay_support_bot
Quick answers 24/7
Legal address
RBY Commerce Ltd.
8 Copthall, Roseau Valley, 00152, Commonwealth of Dominica
Leave a request
Fill out the form — a manager will get in touch, tailor the terms and help with the integration.
