The first step in integration of Payment Page solution is simply by redirecting your customer to the Payment Page. To do that, redirect your customer to the following endpoint:

By redirecting the customer to the endpoint, you initiate the payment process. The customer is presented with a payment flow, which is predefined for your service. The flow is determined by **API key** parameter which is issued to you by Centili.


Available [flows and mandatory steps](🔗) are depending on particular country and operator's regulations and rules.

You can check our site for [available flows and technologies](🔗).

**API key** is the only mandatory parameter, and is defined and issued for each service separately. By adding the **API key** parameter, you should get a redirect URL, similar to one shown in the following example:

The resulting URL will automatically open a localized page in language of the country where you opened it from. The customer should be presented with the page that looks like this:


Example Payment Page - Entry page

In case of successful initiation of the payment process, Centili will complete all the steps needed for successful transaction.

There is a variety of optional parameters that you could use to communicate with Payment Page and control its behavior. The following table shows a complete list of parameters which can be used with the endpoint:

**apikey**stringCentili issued service key, unique for every payment service. Consists of alphanumeric characters and counts up to 32 characters.f31a355df6dad07e49ba474db7ff9b07 **mandatory**
**price**decimalBy providing this parameter, price selection step is skipped.1.45optional
**msisdn**stringCustomer phone number. By providing this parameter, MSISDN entry page is skipped. NOTE: The number must be in [E.164](🔗) format, excluding the plus ("+") character.4477781234567optional
**returnurl**stringURL to which user is redirected after payment. In case of GET requests, URL must be URLencoded. Additional query parameters defined by the client and forwarded through returnurl parameter will be passed back when user is returned, with Centili parameters attached.http://www.example.comoptional
**reference**stringA unique identification parameter under your system (pass-through variable).appID1optional
**userid**stringIdentification of the customer.usrId1983 _NOTE: If the value is not set within payment request, this field will contain MSISDN of the particular customer._optional
**redirecttimeout**integerInterval (in seconds) of delay before redirecting to return URL. If this parameter is: _ omitted, user has to click on the button to continue to the content. _ if its value is set to 0, the redirection is done instantly.5optional
**sign**stringRepresents signed string of all concatenated request parameters sorted alphabetically with Centili issued key by using previously agreed encoding algorithm. _NOTE: Please refer to the [signature key generation guide](🔗)._1f7a5457f65f745787h7a7e578optional
**operator**stringMobile Network Operator code. In some cases it is possible to skip MSISDN entry step by providing this parameter. _Please contact your dedicated Centili person for the availability of this parameter for your particular service._ES_VODAFONEoptional
**country**stringBy supplying this parameter, you can verify how the Centili Payment Page will look in a specific country. Expected parameter value is an international country code. _For more details use [official ISO list of country codes](🔗)._ NOTE: If this parameter is omitted, the Payment Page will use _Country GeoIP_ recognition.GBoptional
**language**stringBy supplying this parameter, you can force the localization of Payment Page. Expected parameter value is an international country code. _For more details use [official ISO list of country codes](🔗)._FRoptional
**theme**stringBy supplying this parameter, you set the change of Payment Page appearance. Omitting this parameter results in default theme.blackoptional

## Example

Here is an example of properly set initiation URL:

The example sets the following:

  • forces country to GB

  • sets price to 1.5 GBP, which skips price selection step

  • sets return URL and reference

  • sets theme to black


Example Payment Page with black theme applied

## Next step...

### **[Redirect after Payment](🔗)**