An API (Application Programming Interface) consists of a set of protocols and definitions that allow an application to communicate with another one. This SMS API is designed to send Short Message Services to mobile phones and can be integrated to an existing software.

API Description

With the Deutsche Telekom SMS API, you can send in a few clicks your A2P (Application-to-Person) traffic through our A2P platform. Connect with your customers through the most robust and adopted communication channel and build your use cases based on our SMS A2P platform.

How to Use

In a first step, the service is being offered based on a pre-paid model. To take advantage of this service, simply follow these steps:

  • Create an account on
  • Make a first prepayment
  • Start sending A2P traffic and benefit from the quality of our network
  • The request needs to be authenticated using the API key from your Dashboard. The key is set as a value of the X-API-Key header.


    X-API-Key: WW91ciBBUEkgS2V5IGFzIGNvcGllZCBmcm9tIHRoZSBkYXNoYm9hcmQ=
Technical Description

The A2P API is built on the RESTful architecture. To send a message, an HTTP POST request needs to be sent to a dedicated base URL.

To authenticate any request, you need to use the API key as an authentication header. The API key is stated within the portal once you subscribed to the service.

With the A2P API, you can trigger the below requests:

  • Send a message (POST)
  • Request delivery Reports (GET)

All the relevant details are available in the documentation section at

As long as there is sufficient balance available at your pre-paid account, the API request is being processed. You can easily top up your balance by a new payment.

With the SMS API, an application can query the API and send an SMS to any personal mobile phone world-wide, but SMS messages cannot be responded (one-way only), as mobile virtual numbers are not provided yet.

The usage of the SMS API is only permitted if the sender ID has been verified to assure the ownership of the phone number. This verification process is done via SMS and limited to 50 sender IDs. Alphanumeric sender IDs (e.g. company name or brand) can be used but limited to certain countries, with pre-registration required in some cases; contact for further details.

To verify a phone number, go to In section Outgoing Phone Numbers click on the “+” icon, insert the number in E.164 format and click on Send code. As soon as you receive the verification code on your device, confirm it and the sender ID is validated. It appears in the list of your numbers.

Standard SMS are limited to 160 standard characters; in case of longer SMS, the request can be handled but billed as multiple SMS. Please note that 160 characters in a single message are only possible when using the 3GPP SMS character set. In case of using other character sets, an SMS will be split into two or more single items, charged accordingly.

Only single recipients are supported, meaning that SMS to multiple recipients must be treated as multiple requests.

Additional Details

There are no base fees applicable to this service.

API requests are charged and deducted from the prepaid account. Please see the Price List per country for details.

Every API request will impact the prepaid balance, even if a wrong recipient number has been used or the sender ID is not supported by the terminating mobile operator.

Prices are simple and transparent. Go to and check our daily updated rates (flat price per country) which are applicable for A2P SMS to the respective destination.

SMS A2P is not designed for aggregators but for software/application developers in direct relation with their end users, therefore reselling is not permitted.

At the moment, the service is limited to German-based customers only and by default any payment will include 19% VAT.

Support is exclusively ensured by email; any technical/commercial enquiry must be sent to and will be treated on best effort.

Component Overview

An overview of all components is shown in the following figure:


Best carrier network

The API uses Telekom Global Carrier's intercarrier voice platform. High-quality routes between all Deutsche Telekom Group companies and almost every other carrier in the world.

Plug & Play

Easily integrate our Calls API: A single request grants access to Telekom's infrastructure and best connectivity between carriers.

Programmable API

The Telekom Telephony service many customers already rely upon. Now with a modern programmable RESTful API.