3CX SIP Trunk Providers - Germany
The SIP Trunk Providers listed for Germany have demonstrated compatibility with the 3CX Phone System. They are categorized as either 3CX Tested, where testing is completed directly by 3CX, or VoIP Provider Tested, where the provider completes the required testing and submits the results to 3CX for review. We recommend choosing a listed provider and checking its interoperability category, capabilities and configuration notes before setup.
For hosted installations, registration-based trunks that do not require a fixed IP are preferred. In certain cases, the public IP address of a Hosted by 3CX system may change. Although uncommon, this can temporarily affect incoming and outgoing calls when using an IP-based trunk.
Read our guide on how to configure a SIP Trunk / VoIP Provider. It explains the general steps for configuring a trunk with 3CX. Some providers have additional requirements, so check the provider’s listing and follow any configuration notes or guides provided.
3CX Tested
These providers have been tested directly by 3CX and meet the applicable technical, support and commercial requirements. Their pre-configured templates are available in 3CX for quick and easy setup.
Capabilities
| SMS Support | No |
| Anonymous Calling | No |
| Clip No Screening Support | Yes |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | Yes |
Important Configuration Notes
Enter the main trunk number as E164.
For the number to be delivered in E164: contact your partner to enable the option “Called Party Format”
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | Yes |
Important Configuration Notes
Enter the main trunk number as E164.
Be sure to follow the configuration guide.
Capabilities
| SMS Support | Yes |
| Anonymous Calling | Yes |
| Clip No Screening Support | No |
| Fax Support | No |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | Yes |
Important Configuration Notes
Enter the main trunk number as E164.
Be sure to follow the configuration guide.
VoIP Provider Tested
These providers have completed the required 3CX interoperability testing and submitted their results for review. Once approved, their pre-configured templates are made available in 3CX. This category does not mean that 3CX has directly tested the provider’s overall service.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | No |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | No |
Important Configuration Notes
Enter the main trunk number in the international number format (e.g. 492115684962).
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - Audio |
| SIP TLS Support | Yes |
| IPV6 Ready | Yes |
| Online Sign-Up & Portal | Yes |
Important Configuration Notes
Deutsche Telekom (CompanyFlex)
Enter the main trunk number as E164.
You can register your CompanyFlex SIP trunk via TCP with a Deutsche Telekom internet connection. If so, select the “Deutsche Telekom (CompanyFlex - VoiceData)” template from the providers' list.
Be sure to follow the configuration guide.
Capabilities
| SMS Support | No |
| Anonymous Calling | No |
| Clip No Screening Support | No |
| Fax Support | Yes - Audio |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | No/Yes |
Important Configuration Notes
DeutscheTelekom (All IP)
Enter the main trunk number in the national number format (e.g. 02115684962).
Be sure to follow the configuration guide.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes (Separate Service) |
| Fax Support | Yes - Audio |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | Yes |
Important Configuration Notes
Deutsche Telekom NGN (SIP Trunk)
Enter the main trunk number as E164.
Be sure to follow the configuration guide.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | Yes/No |
Important Configuration Notes
Enter the main trunk number in the national number format (e.g. 021198765432).
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | Yes |
| IPV6 Ready | Yes |
| Online Sign-Up & Portal | Yes |
Important Configuration Notes
Enter the main trunk number as E164.
Be sure to follow the configuration guide.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes (Separate Service) |
| Fax Support | Yes |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | No |
Important Configuration Notes
Enter the main trunk number as E164.
Registrar address will be provided to you by EWE Tel based on your account.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes (Separate Service) |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | Yes |
| IPV6 Ready | Yes |
| Online Sign-Up & Portal | Yes/No |
Important Configuration Notes
Enter the main trunk number as E164.
Be sure to follow the configuration guide.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | No |
Important Configuration Notes
Enter the main trunk number as E164.
MK Netzdienste supports Clip No Screening as an extra service.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - Audio |
| SIP TLS Support | No |
| IPV6 Ready | Yes |
| Online Sign-Up & Portal | No/Yes |
Important Configuration Notes
Enter the main trunk number as E164.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | No |
| IPV6 Ready | Yes |
| Online Sign-Up & Portal | No |
Important Configuration Notes
Enter the main trunk number as E164.
Authentication based trunk.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - T38 Bypass |
| SIP TLS Support | No |
| IPV6 Ready | Yes |
| Online Sign-Up & Portal | No |
Important Configuration Notes
Enter the main trunk number as E164.
IP based trunk.
Capabilities
| SMS Support | No |
| Anonymous Calling | Yes |
| Clip No Screening Support | Yes |
| Fax Support | Yes - Audio |
| SIP TLS Support | No |
| IPV6 Ready | No |
| Online Sign-Up & Portal | No |
Important Configuration Notes
Enter the main trunk number as E164.
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