SIP Trunk in Germany — Berlin, Munich or Frankfurt Inbound + Outbound

1. What a SIP trunk in Germany actually is

A SIP trunk is the IP delivery pipe between a carrier and your PBX, AI voice agent, or call-control platform; signaling over SIP, audio over RTP. A Germany SIP trunk is the same thing carrying +49 Germany DIDs allocated under Bundesnetzagentur (BNetzA).

DIDHub provides the trunk authentication and SIP transport; Bundesnetzagentur (BNetzA)-compliant number allocation is coordinated through our in-region carrier partners. Your PBX or platform sees a standard SIP trunk; we handle the regulator-side paperwork.

2. Germany regulation: Bundesnetzagentur (BNetzA), KYC, compliance

Bundesnetzagentur (BNetzA) requires KYC documentation before any Germany DID can be allocated. Activation typically takes 1-3 business days. DIDHub handles the document submission and regulator coordination on your behalf.

What people typically use a Germany SIP trunk for:

• German market entry, German buyers strongly prefer Caller IDs starting with their local Vorwahl (089 for Munich-area buyers, 030 for Berlin).
• DACH operations with Vienna and Zurich numbers alongside German ones (we cover Austria and Switzerland too).
• Compliance-friendly for German B2B, many enterprises and the public sector require contact numbers on German Vorwahl.
• AI voice agents targeting Germany, sub-50ms ingress at Frankfurt + a German Caller ID dramatically lifts answer rates.

Germany is a regulated market. The Bundesnetzagentur (BNetzA) requires every German geographic number to be tied to a verified local German address. You must provide proof of address (Anmeldung, utility bill, or business registration) and a copy of ID for the responsible party. DIDHub shows the documents required clearly before checkout, no surprise holds. Activation takes 1-3 business days after document submission. Non-geographic 032 numbers have lighter requirements; 0800 toll-free is the easiest.

For the broader picture across countries, see our guide to international DID compliance & KYC bundles. For the SIP-trunk concept end-to-end, see the DID Number Provider guide.

3. Number types you can route over the trunk

DIDHub supports the standard Germany number types over the SIP trunk:

For a deeper look at how number types differ globally, see DID number types explained.

4. How DIDHub's SIP trunk works in Germany

The technical surface of the trunk is standardised; the Germany-specific choices are the POP, the codec list, and the failover topology.

Ingress POPs

• Frankfurt (primary), lowest in-region latency to Germany endpoints.
• London (failover), secondary route used if the primary path degrades.

Transport & security

• TLS:5061 recommended for any production trunk; UDP allowed for legacy.
• SRTP for media via DTLS-SRTP or SDES.
• SIP authentication: digest registration (PBX behind NAT) or IP-ACL (static peering). See SIP authentication.

Codecs

• G.711 a-law (PCMA), the European default.
• G.722, wideband HD voice on capable endpoints.
• Opus, for AI voice agents and IP-native softphones.
• G.729, available on request.

For the codec deep-dive, see voice codecs explained.

DTMF

• RFC 4733 (telephone-events over RTP) is the default. SIP INFO and in-band DTMF available for legacy interop on request.

Channel concurrency

• Trunks start at 5 concurrent channels and scale to 200 per trunk off the shelf. Larger requires a custom arrangement.
• Channels are independent of DID count; you can carry 200 numbers on a 10-channel trunk if your concurrent-call peak is 10. See multiple concurrent calls on one DID.

STIR/SHAKEN

• Not applicable. The North-American STIR/SHAKEN attestation framework is a US/Canada construct that doesn't exist in Europe. EU trust signals come through national regulator registration and operator-side caller-ID validation.

5. Outbound calling from your Germany trunk

Outbound from a Germany-allocated DID to Germany destinations is allowed within approved use cases. The per-minute economics:

Outbound caller-ID rules

• Your outbound CLI must match a DID you've allocated through the trunk. Setting an arbitrary caller ID is rejected at the SBC.
• Origin-based rating (OBR) applies on cross-border outbound, the regulated EEA tier may apply depending on the source carrier.
• For multi-region operators, see origin-based rating savings.

6. Setup in 6 steps

Asterisk pjsip example

; /etc/asterisk/pjsip.conf
[transport-tls]
type=transport
protocol=tls
bind=0.0.0.0:5061
cert_file=/etc/asterisk/keys/asterisk.crt
priv_key_file=/etc/asterisk/keys/asterisk.key
method=tlsv1_2

[didhub-germany]
type=auth
auth_type=userpass
username=YOUR_DIDHUB_USERNAME
password=YOUR_DIDHUB_PASSWORD

[didhub-germany]
type=aor
contact=sip:sip.didhub.io:5061;transport=tls
qualify_frequency=30

[didhub-germany]
type=endpoint
transport=transport-tls
context=from-didhub
disallow=all
allow=g711a,g722,opus
outbound_auth=didhub-germany
aors=didhub-germany
dtmf_mode=rfc4733
media_encryption=sdes
direct_media=no

3CX SIP trunk template snapshot

# 3CX -> SIP Trunks -> Add SIP Trunk -> Generic SIP Trunk
Trunk name:        DIDHub Germany
Registrar:         sip.didhub.io
Transport:         TLS
Port:              5061
Authentication:    Register/Account based
Auth ID:           YOUR_DIDHUB_USERNAME
Auth password:     YOUR_DIDHUB_PASSWORD
Outbound caller ID: +49 ... (one of your allocated DIDs)
Codecs (priority):  G.711a / G.722 / Opus

7. Integration patterns

Every modern PBX, UC platform, and AI voice stack can authenticate against the trunk:

8. Pricing

Four line items: per-DID monthly rental, per-minute inbound usage on every Germany DID (even landline geographic numbers carry an inbound MOU charge in Germany), channel capacity, and per-minute outbound. Setup is $0 once Bundesnetzagentur (BNetzA) paperwork is approved.

Per-DID monthly

Channel capacity

Per-minute outbound

See section 5 above and the full global rate sheet.

9. Porting an existing Germany number

Existing Germany number? Porting timeline is 2-4 weeks.

• Typical port time: 2-4 weeks
• Required documents: phone bill + LOA + ID + proof of address (Bundesnetzagentur (BNetzA) requirements)
• Cost: port-in fee per number; carrier-side fees may apply

For the full porting playbook (US/UK/EU + the global gotchas), see number porting explained.

10. FAQ

Which POP should I connect to for a Germany SIP trunk?

Frankfurt is the recommended primary; London is the standard failover. Both terminate to Germany via in-region carriers.

How long does activation take for a Germany SIP trunk?

1-3 business days after KYC documents are accepted (or instantly where KYC isn't required). Provisioning the SIP side itself is hours, not days; the variability is on the Bundesnetzagentur (BNetzA)/carrier side.

What codecs should I configure for a Germany SIP trunk?

G.711a / G.722 / Opus as the negotiation list, in that order. G.711a is the regional default for Germany interop.

Can I use my Germany SIP trunk with Microsoft Teams?

Yes, via Microsoft Teams Direct Routing through DIDHub's managed SBC. See Teams Direct Routing.

Can I use my Germany SIP trunk with AI voice agents (Vapi, Retell, ElevenLabs)?

Yes, BYOC SIP trunk works with every major AI voice platform. Bind specific Germany DIDs to specific agents; outbound CLI must match an allocated DID.

How many concurrent calls can one Germany DID handle?

The DID is an address; concurrent-call capacity is set by the channel count on the trunk. A 50-channel trunk with 1 DID can carry 50 concurrent calls to that one number; the same trunk with 200 DIDs can carry 50 concurrent calls across any combination of those numbers.

Does STIR/SHAKEN apply in Germany?

N/A (regional construct). Trust signals come instead through national regulator registration and operator-side caller-ID validation.

Can I port my existing Germany number to a DIDHub SIP trunk?

Yes. Typical Germany port timeline is 2-4 weeks. Required documents vary by number type; contact us for the specific checklist. See number porting explained for the global picture.

What use cases get approved most easily?

Customer service inbound, opted-in callbacks, transactional 2FA, inbound AI voice agents, and Microsoft Teams Direct Routing for registered entities. Cold outbound, unsolicited SMS campaigns, and anonymous-relay setups are routinely rejected.

11. Related country pages