OnPay · gateway

OnPay integration in your web app

An OnPay integration means checkout in your system creates a payment at OnPay and only marks the order paid when their notification is verified. Danish shops use OnPay when they want a sober gateway layer without a huge product suite. That is fine when you have one currency, one flow and an existing agreement. Amounts are set server-side. The callback signature is verified. Timeout: the customer closes the window, and your order must not hang in “pending” forever without a cleanup job. Refunds are logged with a user id in your admin. If you do not have an agreement yet, choose based on MobilePay need and the support you want to call.

If you already have OnPay, start there. A new gateway is KYC and first settlement on top of the build. Payments.

Events
payment.capturedok
invoice.bookedok
click.paidignore
The callback is verified before status flips to paid.

Build rules for an OnPay integration

  • Amount is set server-side
  • Callback signature is verified
  • A timeout job clears orders that hang in pending
  • Refunds are logged with a user id in your admin
1

Create payment

The backend sends amount, currency and order id to OnPay.

2

Window

The customer pays or closes. Close is not the same as declined.

3

Callback

You verify the signature and write status. Only then is the order paid.

4

Cleanup

A job finds orders that never got a callback and returns them to the cart.

The notification is the truth, not the browser return.
OnPayQuickPayPensoPay
Sober Danish gateways. Choose by agreement and MobilePay.

OnPay or QuickPay

If you do not have an agreement yet, choose by MobilePay need, settlement and the support you want to call. If you have OnPay, start there. QuickPay integration is the comparison, not an automatic upgrade.

OnPay in a Ceptiv package is 1 integration. Small 18,000 DKK + 600 DKK/month. The transaction fee is OnPay’s.

Hanging orders and the timeout job

What separates a finished OnPay integration from a demo link is the job that clears “pending” after 30–60 minutes and gives the customer a way back. Write it in the brief. Get a quote · Pricing.

FAQ: OnPay integration

OnPay or QuickPay?

If you have OnPay, start there. If you have no agreement, choose by MobilePay, settlement and support.

Can we trust that the customer returns in the browser?

No. The callback is the truth. The browser return is a polite redirect.

What happens if the customer closes the window?

Without a timeout job the order hangs in pending. With the job it returns to the cart.

Build OnPay into the web app