Austria: SIP providers and connecting a number to the PBX

This page continues the general guide to connecting a provider's number to the PBX: that page covers what is the same for every carrier — the two trunk modes, what to ask the provider, what to enter in the form, network requirements and how to test the link. Here is the Austrian part: who sells a number with a SIP trunk in the country, what that carrier issues and what of it goes into Telephony → "Trunks and connections" → "Add provider".

The data was collected on 9 September 2026 from carrier documentation and materials of the regulator RTR; links are in the "Sources" section.

In short#

• You can buy a number with a SIP trunk in Austria. A venue needs neither a licence nor a registration: the telecom service is sold by a carrier, and it is the carrier — not you — who notifies the regulator (RTR).
• The market is split in two. The incumbents (A1, Magenta, Drei) sell a trunk as an add-on to their own internet access, while the alternative carriers (easybell Österreich, yuutel, peoplefone, Innosoft, media.tel, fonira, Tele-Tec) sell it over any connection. For a PBX in the cloud you want the latter.
• If you have not picked a carrier yet, take easybell Österreich. It is the only one in the country that publishes a complete ready-made Asterisk configuration, and the codecs in it are exactly ours (a-law, u-law, G.722); the price is €1 per month per voice channel (two minimum), with no setup fee and no minimum term. Fallbacks are Magenta and yuutel.
• The main local pitfall is "a trunk only on our own access". Drei requires both signalling and voice to be encrypted when the trunk runs over someone else's access, and our PBX does not support TLS or SRTP trunks — that combination will not work. For A1 the contract declares its own router as the network termination point, meaning the product is designed for A1 access.
• The second pitfall is non-standard ports. Drei explicitly does not support the standard UDP 5060 (it uses 5083), Innosoft uses 5160, and yuutel uses 5084 for a PBX without NAT. Leaving the default 5060 breaks the connection silently.
• The third is verification of numbers arriving from abroad. Since 1 September 2024 Austrian carriers must verify Austrian numbers on calls coming from abroad: if the right to the number is not confirmed, the number is not displayed, and proven spoofing ends the call. Inbound calls to an Austrian number bought abroad work fine, but to display it on outbound calls you need an Austrian carrier.

Numbers in Austria#

• Country code — +43, national prefix — 0, international prefix — 00.
• A national number = area code (Ortsvorwahl) without the leading zero + subscriber part. Vienna — 1, Graz — 316, Klagenfurt — 463, Innsbruck — 512, Salzburg — 662, Linz — 732, Mödling — 2236, Baden — 2252, Dornbirn — 5572, Wels — 7242.
• The subscriber part is usually 5 digits, 6 in the cities listed above and 7 in Vienna. A block of extensions (Durchwahl) is appended to the right of the head number.
• Non-geographic ranges: 0720 — nomadic (the lawful option for VoIP and cloud PBXs), 05 — a nationwide company number, 0800 — toll-free for the caller, 0810 and 0820 — shared cost, 0900, 0901, 0930, 0931 and 118xx — premium rate.
• Mobile — the ranges 0650–0688 (including 0660, 0664, 0676, 0680, 0699).
• Emergency numbers — the pan-European 112 plus the national 133 (police), 122 (fire) and 144 (ambulance). They are dialled without any prefix: yuutel warns that a call with an area code in front will land in the centre for that area code rather than the one covering your address.

On the "Lines" tab a number may be entered in any format: the PBX matches the last seven digits. ⚠️ In small areas where the subscriber part is 5 digits, those seven digits also capture the tail of the area code — two numbers from different areas that share the same tail will collide. In Vienna (7 subscriber digits) and on Durchwahl blocks there is no such problem.

Who sells a number with a SIP trunk#

The first five rows are carriers whose server address and mode are known in advance: their cards are below. The other Austrian carriers issue settings by letter or in the portal after a contract is signed — they have a separate section.

easybell Österreich#

A Berlin carrier (a brand of the Dstny group) with an Austrian arm and Austrian support. Ordered online, with no setup fee and no minimum term, the first 30 days without a monthly fee; the price is €1 per month per voice channel (2 minimum, 3000 maximum, scaled monthly). CLIP no screening, fax to e-mail, voicemail and conferences are included. It is the only Austrian carrier publishing a complete Asterisk configuration with the codecs a-law, u-law and G.722 — exactly ours.

What to enter in the admin panel

What to set up at the provider: order a Business SIP Trunk → get a landline number and, if needed, a Durchwahl block → in the portal under "Telefonanschluss" → "Verbindungen" → "Konfiguration" set "Rufnummernanzeige (CLIP)" to "PBX bestimmt Anrufer-ID (CLIP No Screening)" and "From Display (Default)" → check that your plan has enough channels → point the numbers at the trunk.

Pitfalls ⚠️ Switching the caller ID mode is mandatory: only in the "From Display" variant does the carrier take the number from the ordinary call field, which is what makes the "Display as" rule work. The Austrian help article carries a German copy of the sample configuration — with the address voip.easybell.de and German numbers; the Austrian values (sip.easybell.com, a number in the 0043… format) appear only in the comments next to it, so the sample cannot be copied as a whole. The carrier's second address, pbx.easybell.de, is its own cloud PBX, not a trunk. One SIP username equals one trunk, and the number of simultaneous calls equals the number of channels you pay for. Touch tones use RFC 2833, as we do; sending tones via SIP INFO must be switched off in the portal. Source: Asterisk 22 setup, VoIP expert settings, SIP Trunks pricing — 09.09.2026.

yuutel#

A Vienna business telephony carrier (ATMS was merged into it — atms.at now leads to yuutel.at). The product for a third-party PBX is yuuconnect Business Trunk: €59.00/month for 10 channels, then €5.90/month per channel, €299 one-off for setup, monthly termination, free porting of numbers from Austria, Germany and Switzerland. It has the most detailed public trunk specification in the country — ports, codecs, headers and NAT behaviour.

What to enter in the admin panel

What to set up at the provider: order a yuuconnect Business Trunk and the number of channels → state Business Trunk Profil 1 in the order (the profile decides where the carrier expects the displayed number; in the first one it is read from the ordinary call field) → get your SIP account domain and credentials → if needed, order the G.722 codec and the removal of the block on calls outside Europe.

Pitfalls ⚠️ Registration is mandatory by law on reachability: "static routing to fixed IP addresses is not supported", and without an active registration even an outbound call will not go through. The port is the main trap: 5060 is meant for PBXs behind NAT, ours works without it, and "left it at 5060" means silence here. At yuutel the account domain and the proxy address are different things, and the proxy must never be put into call headers; our form has a single field, so the first trunk is worth checking with a SIP trace. The carrier does not support SIP call transfer (REFER) — build transfers inside your own PBX; calls outside Europe and to Austrian premium numbers are blocked by default and unblocked only via a support ticket. Source: Technischer Anhang zur Leistungsbeschreibung yuuconnect, SIP Trunk pricing — 09.09.2026.

Magenta Telekom#

Austria's second largest carrier (T-Mobile Austria GmbH in the documents). The product for a third-party PBX is Business Voice SIP; all settings and call records live in the web portal csc.magentabusiness.at. What matters for us is that the allowed address is changed by the customer themselves in the portal: that matches the dedicated-PBX-with-static-IP model exactly.

What to enter in the admin panel

What to set up at the provider: order Business Voice SIP → set the SIP password in the portal → put the static IP of your PBX into the "Freigeschaltene IP" field (the "Server" tab of the Telephony section) → order CLIP no screening and T.38 fax separately if needed → point the numbers or the Durchwahl block at the trunk.

Pitfalls ⚠️ There is exactly one allowed address: "for security reasons, registration is only possible from this IP address". Moving the PBX to another region or cloud means editing it by hand in the portal, otherwise registration simply fails. The codec is G.711a, and the carrier asks for it to be first and for G.722 to be excluded; our codec set is global and does negotiate G.711a, but check the audio on the very first test call. The inbound number arrives in the national format with a leading zero (0662123456) — the line is still matched by the last seven digits, but fill in the outbound rule in the format the carrier asks for. CLIP no screening and fax are enabled only on a separate request. Source: Leistungsbeschreibung Business Voice SIP, Magenta Business Voice SIP configuration in the Unify guide — 09.09.2026.

peoplefone Austria#

A Swiss group with an Austrian legal entity and its own Austrian numbering; besides Austrian numbers, a single account can hold numbers from more than 60 countries. The products are peoplefone SIP TRUNK and ELASTIC SIP-TRUNK; the carrier itself stresses that only three values are needed to connect — proxy, username and password.

What to enter in the admin panel

What to set up at the provider: create a SIP line and a number → enable the "SIP-TRUNK" type on the line (free of charge, switched on by support or a partner) → enable "CLI OPEN" so your number is shown on outbound calls → assign the number an address in the "Notrufe" section — it decides where a 112 call is delivered.

Pitfalls ⚠️ A forgotten "SIP-TRUNK" checkbox on the line is the most common cause of "calls come in but extensions do not work": without it the carrier sends headers as if to a single handset, and calls cannot be split across lines. The platform codecs are a-law, u-law, G.722 and G.729; our set passes entirely (their Opus works only inside their own network, which does not concern us). Touch tones use RFC 2833. The carrier itself sends keep-alive packets every 30 seconds. The Austrian and Swiss platform addresses overlap (95.128.80.0/29) — do not mix up the two arms when describing your network to the carrier. Source: peoplefone SIP TRUNK, FreePBX / chan_pjsip setup, firewall rules — 09.09.2026.

Innosoft (MyInno Trunk)#

A Tyrolean carrier with the MyInno Trunk product — a trunk for any SIP PBX; everything is managed in the MyInno web application, billing is per second, and a free trial installation is available. The carrier publishes its technical parameters in its own network checklist.

What to enter in the admin panel

What to set up at the provider: order a MyInno Trunk (a free trial installation is possible) → take the "Anmeldedaten" in MyInno → choose how the number is signalled — the display name in the From call field, not a service header → point the numbers at the trunk.

Pitfalls ⚠️ Two details break the connection silently: port 5160 and the letter u in front of +43… in the username (easily lost when copying). The codecs are G.711 a-law and µ-law and touch tones use RFC 2833: our set fits, the carrier has no G.722. If you want several Innosoft trunks on one PBX, the carrier requires "Multi Trunk Nutzung" to be enabled and the number to be signalled via the P-Preferred-Identity service header, which our PBX does not send — so keep one Innosoft trunk per PBX. The carrier probes your PBX with a service request every 60 seconds and expects an answer within 2 seconds. Source: Netzwerk-Checkliste für SIP Trunks v1.21, SIP Trunk für VoIP-Telefonanlage — 09.09.2026.

Contract-only carriers: A1, Drei and others#

These carriers do have SIP trunks, but the server address, username and password are issued by letter or in the portal after a contract is signed — there can be no "what to enter" table here. Ask the account manager for the settings using the list in "What to ask the provider" and enter them into the same form as for everyone else.

A1 Telekom Austria#

The incumbent. A1 SIP Trunk comes in 3/15/30/70/120 voice channels, with a minimum term and automatic 12-month renewal, and at least one geographic number is mandatory. The mode is registration, but the technical interface description ("A1 SIP Guideline – Registrierende Anschaltung") is not published and is issued to the customer on request: without it the settings cannot be guessed. The credentials arrive by letter. Displaying your own number on outbound calls is supported — the carrier describes it as "a number programmed in the IP PBX as additional information".

⚠️ For a cloud PBX the product is problematic: the contract declares an A1 router as the network termination point, and that router remains A1's property — meaning the trunk is designed for A1 access rather than for a PBX at a third-party provider. Before ordering, get A1's confirmation that registration from the internet is allowed. On top of that, the product is closed to micro and small enterprises and to non-profits — a small venue simply will not be sold it.

Drei (SIP Connect)#

The product is not suitable for our PBX. Drei explicitly requires that both voice and signalling be encrypted when SIP Connect runs over a third-party internet access, and our PBX does not support TLS or SRTP trunks — see "Network and compatibility". Even with encryption, the carrier additionally requires your address to be unblocked in advance, and it supports neither TCP nor the standard UDP port 5060: its signalling runs on UDP 5083 (the encrypted variant is 5088). The trunk address arrives in the welcome letter as a domain for which Drei itself publishes the necessary DNS records. The displayed number is read from the ordinary call field and is always treated as international, while sending the P-Asserted-Identity service header is forbidden.

International providers with Austrian numbers#

Almost every international carrier sells Austrian numbers. Their trunk settings are the same for all countries — take them from the provider's card in the admin catalogue or from "Add provider"; what follows is the Austrian specifics only:

• DIDWW sells Austrian landline, national, toll-free 0800 and international toll-free UIFN numbers. It has no Austrian mobile numbers. Landline and national numbers require number registration (company and address documents); 0800 does not.
• Telnyx maintains a dedicated Austria requirements page — check the documents there before paying.
• Twilio, Vonage, Plivo, Bandwidth, Sinch, Infobip, Zadarma and Sonetel list Austrian numbers in their general coverage tables; check the country requirements with the provider itself when ordering.
• Displaying an Austrian number from abroad does not work. Since 01.09.2024 Austrian carriers verify Austrian numbers on calls arriving from abroad: if it is not confirmed, the number is not shown to the called party. Inbound calls to such a number work fine, but make outbound calls with it through an Austrian carrier.
• A landline number is tied to its area. For a foreign company without an Austrian address it is easier to take a nomadic 0720 number (lawful for VoIP) or an 0800 one than a landline number of a specific city.
• Emergency calls at international providers are a separate service or are not offered at all. If 112 has to work from the number, take an Austrian carrier or order the emergency service explicitly.

Number porting#

• Porting a number to another carrier is the subscriber's right, and the procedure is described in the Nummernübertragungsverordnung (NÜV). The reference from the old carrier that the new one needs (NÜV-Information) is free and valid for 90 days; issued electronically it arrives within 20 minutes during business hours, by post it is sent the next working day.
• In practice porting at the alternative carriers takes about 14 days end to end; urgent porting exists but by arrangement.
• The new carrier initiates the port using the form you sign; the old contract is terminated at the moment of porting.
• A landline number ports only within its own area. A1 explicitly limits keeping a number to "within the same area code": moving the venue to another city means a new number.
• Porting is often already included in the trunk price: yuutel ports numbers from Austria, Germany and Switzerland for free, and fonira offers either porting or a free new number.
• Emergency calls are tied to an address. yuutel delivers 112 and 133 to the centre covering the address of the trunk's head number, and peoplefone requires an address to be assigned to every number. If you move, update the address with the carrier, otherwise the call will land in the wrong centre.

Rules and paperwork#

If it does not work#

Causes that do not depend on the country are in "If calls do not go through"; the SIP trace in the trunk menu is described there too. Checking the address and port — "Test the link".

Frequently asked questions#

Which carrier should I choose if nothing is connected yet?#

easybell Österreich. It is the only one in the country publishing a ready-made Asterisk configuration, and its codecs are exactly ours; the port is standard, ordering is online, and the entry threshold is two channels at €1 per month with no setup fee and no minimum term. The fallbacks are Magenta (if you want a big carrier and are fine with a single allowed address) and yuutel (if you need channels by the dozen).

Can I get an Austrian number if my company is registered outside Austria?#

At a local carrier — hardly: the contract is signed with an Austrian entity, and a landline number is issued with a binding to the area where the venue is located. None of the carriers we checked publishes a procedure for foreign companies. The practical route is an international provider with Austrian numbers; it will ask for documents for a landline number too, so a nomadic 0720 or a toll-free 0800 number is easier.

Why is Drei unsuitable, and what about A1?#

Drei requires both signalling and voice to be encrypted when working over a third-party internet access, and our PBX does not support TLS or SRTP trunks — the combination will not work. A1 is technically registration-based, but the contract declares its own router as the network termination point, the technical description is issued only on request, and the product is closed to micro and small enterprises. Order either incumbent only after a written "yes" to registering a PBX from the cloud.

Can I display a different number on outbound calls?#

Only another number of your own, one you have the right to: the law requires the correct number to be transmitted and the carrier to verify it. It also has to be enabled technically: at easybell it is the "PBX bestimmt Anrufer-ID" and "From Display" mode, at peoplefone "CLI OPEN", and at Magenta and A1 a separate request. At yuutel in profile 2 and at Innosoft with several trunks the number is read from a service header our PBX does not send — there the trunk number will be shown.

How many channels does a venue need?#

A channel is one simultaneous call; a restaurant usually needs 2–3. At easybell channels are bought one by one (€1/month, 2 minimum), fonira's base plan has 4, and yuutel's entry package is 10 straight away. Agree the number of channels before signing: "calls stop going through after the second one" is a plan limit, not a fault.

Why is the port not 5060 at some carriers?#

That is the carrier's own choice, and it is not a typo: Drei states plainly that it does not support the standard UDP 5060 (it uses 5083), the Innosoft trunk listens on 5160, and yuutel keeps 5060 for PBXs behind NAT and 5084 for PBXs with a public address such as ours. Fill in the Port field of the trunk form from the carrier's documentation rather than leaving the default.

Sources#

All links checked on 09.09.2026.

Carriers

• easybell Österreich — Asterisk 22 setup (full sample configuration): https://www.easybell.at/hilfe/telefon-konfiguration/ip-telefonanlagen-fuer-unsere-sip-trunks/antwort/asterisk-telefonanlagen/
• easybell Österreich — VoIP expert settings (registrar, ports, codecs, tones): https://www.easybell.at/hilfe/konfiguration/allgemein/voip-experteneinstellungen/
• easybell Österreich — SIP Trunks: pricing and channels: https://www.easybell.at/sip-trunks/
• yuutel — Technischer Anhang zur Leistungsbeschreibung yuuconnect: https://dokucenter.yuutel.at/space/Dokucenter/2238492602/Technischer+Anhang+zur+Leistungsbeschreibung+des+Produkts+yuuconnect
• yuutel — SIP Trunk: pricing and features: https://www.yuutel.at/sip-trunk
• Magenta Telekom — Leistungsbeschreibung Business Voice SIP: https://www.magenta.at/content/dam/magenta_at/pdfs/business/lb/festnetz-telefonie/202111_LB_Business_Voice_SIP.pdf
• Unify — Magenta Business Voice SIP configuration (the text of the carrier's welcome letter): https://wiki.unify.com/images/5/5a/SIP-Trunk-Configuration-AT-Magenta.pdf
• peoplefone Austria — SIP TRUNK: https://support.peoplefone.com/aut/peoplefone-sip-trunk/
• peoplefone Austria — FreePBX / chan_pjsip setup: https://support.peoplefone.com/aut/drittanbieter-produkte/freepbx/
• peoplefone Austria — firewall rules (ports, address ranges): https://support.peoplefone.com/aut/fehlerbehebung/firewall-regeln/
• Innosoft — Netzwerk-Checkliste für SIP Trunks v1.21: https://www.innosoft.at/assets/help/netzwerk-checklist-sip-trunk.pdf
• Innosoft — SIP Trunk für VoIP-Telefonanlage (MyInno Trunk): https://www.innosoft.at/festnetz/business/sip-trunk-fuer-voip-telefonanlage
• A1 Telekom Austria — Leistungsbeschreibung A1 SIP Trunk: https://cdn21.a1.net/documents/37417/187135/LB-A1-SIP-Trunk.pdf
• Drei — Leistungsbeschreibung SIP Connect (as of 07/2026): https://www.drei.at/media/common/business/sip-connect/sip-connect-lb-2.pdf
• media.tel — SIP-Trunking: https://www.mediatel.at/produkte/telefonleitung-sip/sip-trunking/
• media.tel — Austrian numbers: types, costs, porting: https://www.mediatel.at/loesungen/ratgeber/oesterreichische-rufnummern-arten-kosten-portierung/
• fonira — IP-Telefonie (SIP trunk, pricing): https://www.fonira.at/ip-telefonie
• fonira — Leistungsbeschreibung SIP-Trunk: http://fonira.at/cms/wp-content/uploads/LB-SIP-Trunk.pdf
• Tele-Tec — SIP Trunk: https://www.tele-tec.at/sip-trunk/
• my Tweak Telekom — VoIP, SIP trunks, cloud PBX: https://mytweak.at/
• IP Austria — IP Voice / SIP Trunks: https://www.ipaustria.com/en/
• Enreach/Swyx — interoperability profiles of Austrian carriers (media.tel, Tele-Tec, myTweak, IP Austria, net-cloud, PCH, Russmedia, NFON): https://service.swyx.net/hc/de/sections/360003167320-SIP-Provider-AT-CH

Regulator and law

• RTR — notification of starting operations (§ 6 TKG 2021): https://www.rtr.at/TKP/was_wir_tun/telekommunikation/anbieterservice/allgemeingenehmigung/Allgemeingenehmigung.de.html
• RTR — numbering administration, ranges and calling number transmission: https://www.rtr.at/TKP/was_wir_tun/telekommunikation/nummerierung/FAQNum/Allgemein.de.html
• RTR — the anti-spoofing regulation in force since 01.09.2024: https://www.rtr.at/TKP/presse/pressemitteilungen/presseinformationen_2024/pinfo29082024tkp.de.html
• RTR — allocation of numbers to carriers and subscribers: https://www.rtr.at/TKP/was_wir_tun/telekommunikation/anbieterservice/rufnummern/Rufnummern.de.html
• Changes to the number porting procedure (validity of the NÜV-Information): https://www.tarife.at/blog/portierung-der-rufnummer-aenderungen-bei-der-nuevi

International providers

• DIDWW — regulatory requirements for Austria: http://www.didww.com/resources/regulatory-requirements/Austria
• Telnyx — Austria DID requirements: https://support.telnyx.com/en/articles/5463877-austria-did-requirements

Related pages#

• Connecting a provider's number to the PBX — the common steps, trunk modes, network, testing the link.
• Setting up SIP phones — how to connect desk phones and DECT handsets to extensions.