> **Description:** Learn how to create and start payment flows, including best practices for payment screen design and user experience optimization in Vipps MobilePay.

# Initiate payment

When you create a payment with the user's phone number,
they will get a notification in their Vipps  or MobilePay  app.
If you don't have their phone number, you can specify that they should be directed to the
[Vipps MobilePay landing page](https://developer.vippsmobilepay.com/docs/knowledge-base/landing-page.md), where they enter their phone number and then open their own app.

Within the user's Vipps or MobilePay app, they will be presented with a payment screen with the following details:

* *Sales unit name* - The name of the sales unit.
  A merchant can have multiple sales units to represent different physical shops,
  vending machines, collection points, services, and similar.
* *Merchant name / Organization name* - The name of the merchant that owns this sales unit.
* *Merchant Serial Number* - The Merchant Serial Number (MSN), or ID number for a sales unit.
* *Description / `reference` (`orderId`)* - The description or `orderId` associated with this purchase, as provided by the merchant.

Annotated Vipps MobilePay app screenshots. Payment screen: labeled with merchant logo, sales unit name, and order description, with a Pay button and card selection. Receipt: shows payment marked as Paid.

When the user authorizes the payment, the amount will be reserved.
It will remain in the *reserved* state until it is [captured](https://developer.vippsmobilepay.com/docs/knowledge-base/reserve-and-capture.md) or [cancelled](https://developer.vippsmobilepay.com/docs/knowledge-base/cancel.md).

**NOTE**

A payment must be handled within the [payment capture deadlines](https://developer.vippsmobilepay.com/docs/knowledge-base/reserve-and-capture.md#capture-deadlines).
If it's not captured or cancelled within this time, it will be automatically cancelled.

After initiating a payment, you should implement polling to retrieve payment details and track
the payment status. This is essential for knowing when a payment has been completed, failed, or
cancelled.

**Important:** Each payment is unique per sales unit (MSN). Make sure you use the correct API keys
for the sales unit that initiated the payment. Using API keys from a different sales unit will
result in an error.

See:

* [Polling guidelines](https://developer.vippsmobilepay.com/docs/knowledge-base/polling-guidelines.md) - Best practices for checking
  payment status
* [Can't find a transaction?](https://developer.vippsmobilepay.com/docs/knowledge-base/portal.md#cant-find-a-transaction) - Troubleshooting missing
  transactions
* [errorCode 35 "Requested order not found"](https://developer.vippsmobilepay.com/docs/knowledge-base/errors.md#errorcode-35-requested-order-not-found) -
  Technical details for developers

*Capture* is the operation that moves the money from the customer's account to the merchant's account.
This can take a few days, depending on your bank.
For more details, see the [Capture](https://developer.vippsmobilepay.com/docs/knowledge-base/reserve-and-capture.md) section.

You can also cancel payments that should not be processed.
For more details, see the [Cancel](https://developer.vippsmobilepay.com/docs/knowledge-base/cancel.md) section.

For problems with your integration, see
[HTTP response codes and errors](https://developer.vippsmobilepay.com/docs/knowledge-base/errors.md), which covers payment failures, API errors,
and troubleshooting guidance.

## API guides

Creating a payment can be done with any of the following APIs:

* [ePayment API: Create payment](https://developer.vippsmobilepay.com/docs/APIs/epayment-api/api-guide/operations/create.md)
* [Recurring API: Create a charge](https://developer.vippsmobilepay.com/docs/APIs/recurring-api/recurring-api-guide.md#create-a-charge)

Some APIs can use credit cards for payments.
See [Card payments](https://developer.vippsmobilepay.com/docs/knowledge-base/payments.md#card-payments) for details.

> **Full site overview:** For every page in this documentation, read [https://developer.vippsmobilepay.com/llms.txt](https://developer.vippsmobilepay.com/llms.txt).