Estonia: SIP providers and connecting a number to the PBX

This page continues the general guide on connecting a provider's number to the PBX: that page covers everything that is the same for any operator — the two trunk modes, what to ask the provider, what to type into the form, the network requirements and how to verify the link. Here are the Estonian specifics: who sells a number with a SIP trunk in the country, what such an operator hands over and what of it goes into Telephony → "Trunks and connections" → "Add provider".

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

In short#

• You can buy a number with a SIP trunk in Estonia, and the venue needs no permits for it. There is no separate "VoIP licence": a communications business starts with a notification to the regulator (TTJA), and the one who files it is the operator you buy the number and the channel from, not you.
• Estonia is a rare case where the incumbent itself published the full trunk parameters. The Telia Eesti "Vahendusjaama IP ühendus" (ViPÜ) product is documented on the site down to the last line: server proxy.pbx.elion.ee, port 5060 over UDP or TCP, registration mode, mandatory G.711 A-law codec, RFC 2833 tone dialling — all within what our PBX speaks. The prices are there too: €1.85 per month for a number, €5.55 per month for a channel, excluding VAT.
• The main trap of the country is that Telia requires a special header on outbound calls. ViPÜ accepts an outbound call only if the invitation carries a P-Preferred-Identity header with the registered address of the account. The PBX does not send it by default, so the picture will be misleading: registration is up, inbound calls arrive, and outbound calls are rejected. The header is enabled on the server side — write to support before your first outbound calls.
• The second trap is the length of the number. Estonian fixed numbers are seven digits long, which is exactly what the PBX matches a line by — a perfect fit. Mobile numbers, however, can be eight digits (5xxx xxxx and numbers starting with 81–84): their first digit falls outside the match, so two such numbers on one trunk become indistinguishable.
• The market has three operators, and two of them publish no trunk at all. At Elisa both "PBX services" (IP Centrex, Elisa Ring) are its own cloud exchanges, and at Tele2 there are "Kontoritelefon" packages without a single published SIP parameter. The plan "we will take a trunk from any large Estonian operator" does not work here.
• The local alternative to Telia is CSC Telecom Estonia with a cheap entry point (€3.90 per month for one simultaneous call and two local numbers), but it hands over the parameters and the authorisation mode only after a contract.
• The fastest route is an international +372 number: DIDWW (national, mobile, toll-free) or Zadarma (Tallinn +372 6…). Twilio has no Estonian geographic numbers at all — only mobile and 800 ones.

Numbers in Estonia#

• Country code — 372, international prefix — 00 (or +).
• The numbering plan is closed and has no area codes, and there is no national trunk prefix 0 either: inside the country the number is always dialled in full, with no prefix.
• Length. Fixed numbers are 7 digits, mobile ones are 7 or 8; the plan's maximum for a national number is 12 digits (that is machine-to-machine communication).
• Mobile numbers start with 5, and since 2008 eight-digit ones starting with 81–84 have been issued as well. There are not many of them (Telia has around 25,000, mostly on prepaid cards), but you may still run into one.
• Geographic numbers: Tallinn numbers start with 6, Tartu ones with 7. Ask your provider for the full list of number ranges when ordering a number.
• Special number types: 800 — free for the caller, 900 — premium rate, 112 — the single emergency number, 116… — harmonised social numbers, 118… — directory enquiries, 1247 — the state information line.
• In E.164 an Estonian number looks like +372 plus the same 7–8 digits.

On the "Lines" tab the number may be entered in any form: the PBX matches the last seven digits, so both +3726123456 and 6123456 find the same line.

⚠️ The eight-digit trap. For a seven-digit fixed number the match is perfect: the tail equals the whole number, nothing can be confused. For an eight-digit mobile number the first digit is dropped — 5123 4567 and 8123 4567 produce the same tail 1234567 and become one line for the PBX. The call is still accepted, but routing rules may go to the wrong place. A practical rule: check the tails if you put several mobile numbers on one trunk, or split them across separate trunks — see "Add the number and routing".

Who sells a number with a SIP trunk#

There are three cards with ready-made fields below: the parameters are publicly known for both Telia products and, in part, for Apifonica. The rest hand them over after a contract — see "under contract".

Telia Eesti — ViPÜ (Vahendusjaama IP ühendus)#

The incumbent's regular product: "connect your own IP exchange to the telephone network over the internet". The service terms say it plainly: a vahendusjaam is an exchange owned by the customer, while Telia issues a number or a range of numbers, a user name and a password. Identification runs on the login, the password and the IP address of the connection. There are two pricing profiles: "ViPÜ number" — a per-number fee (€1.85 per month excluding VAT) with a hard cap of three simultaneous calls per number, and "ViPÜ kanal + DDI" — a per-channel fee (€5.55 per month) plus €0.06 per number in the range; the number of channels is the number of simultaneous calls.

What to enter in the admin panel

What to set up at the provider: order ViPÜ in the "number" or "kanal + DDI" profile and receive a login and a password → in the "teenuste portaal" enter the static IP of your PBX (the "Server" tab in the "Telephony" section, the "Static IP" field) → there you may also enable or disable the IP check for that SIP account → point the required numbers of the range at the trunk and add them here as lines, using the full seven-digit numbers.

What is included: the mandatory codec is G.711 A-law, tone dialling is RFC 2833, SIP signalling runs over UDP and TCP on port 5060, media uses the UDP range 50000–55999 on Telia's side, and session timers follow RFC 4028. Our codec set (G.711 A-law, G.711 µ-law, G.722) matches this, so no transcoding is needed. For resilience Telia publishes not one address but a queue of servers in DNS — the PBX picks the next one itself.

Pitfalls ⚠️ The main one is ⚠️⚠️ the mandatory P-Preferred-Identity header: Telia requires every outbound invitation to carry the registered address of the account, and without it rejects outbound calls while still accepting inbound ones. The PBX does not send this header by default; it is enabled on the server side — write to support before your first outbound calls. The second one: the IP check is on by default, so registration may succeed while outbound calls do not, until the address of the exchange is entered in the service portal; when the PBX moves, the address has to be updated. The third: there is one pilot account per exchange, so several separate trunks for one venue cannot be built on ViPÜ — numbers are told apart by the DDI range, not by registrations. And remember the cap of three simultaneous calls in the "ViPÜ number" profile: a venue with a call queue needs the channel-based profile. Sources: the ViPÜ page and the service terms (PDF) — 09.09.2026.

Telia Eesti — Ärilahendus VoIP#

Telia's second, simpler product: internet calling where each number gets its own SIP account in the form number@elion.ee. This is not a trunk with a range of numbers, but our PBX sees such an account as an ordinary trunk with registration: one trunk — one number. The parameters are published in the official document "Internetikõneteenuste kasutamise tingimused ja parameetrid".

What to enter in the admin panel

What to set up at the provider: order the service for the required number, get the account password, and ask for G.711 codecs (the document allows "G.711 and/or G.729", and of that pair only G.711 works for our PBX; Telia's fax service uses G.711 A-law in any case).

What is included: SIP signalling over UDP and TCP on port 5060, media in the UDP range 50000–55999, and a requirement to keep the NAT session open for at least 70 seconds or send keep-alive packets. For a cloud PBX that does not matter: it sits on a public static address.

Pitfalls ⚠️ The product is "per number", not "per exchange": ten numbers mean ten trunks with separate passwords. The service has historically been sold together with Telia's office internet access — for a cloud PBX that is an unnecessary tie, so when choosing between the two Telia products take ViPÜ; whether the account is sold separately from Telia's internet is a question for the seller. And do not confuse it with Telia's mobile VoIP (an account in the form ims…3gppnetwork.org): that is the IMS of a mobile number, not a trunk. Source: Telia's internet calling parameters (PDF) — 09.09.2026.

Apifonica (Dzinga)#

An operator with its own licensed network and an Estonian legal entity: the Apifonica business was transferred on 1 June 2018 to SmartTel Plus OÜ (Estonia), which trades under the Dzinga brand. The product is a SIP trunk — "connect your PBX or contact centre to over 190 destinations"; Asterisk and FreePBX are named among the supported systems in plain text. The commercial terms are friendly: no setup fee, no contract term and no minimum volume, pay per minute; the platform is hosted in Germany.

What to enter in the admin panel

What to set up at the provider: create a trunk in the portal → choose the mode (by login or by your IP) → buy or port an Estonian number and point it at the trunk → check the codecs: we need G.711 A-law, G.711 µ-law or G.722.

What is included: the provider's requirements for the customer side are open UDP 5060 and media ports, SIP ALG switched off on intermediate equipment and about 100 kbit/s per call. Our PBX sits in the cloud on a public address, so nothing is required from the venue's own network here.

Pitfalls ⚠️ The codecs and the server address are not published, so compatibility is confirmed only on a live trunk — ask for the parameters in writing when ordering. Check that Estonian numbers are actually available before buying: the legal entity is Estonian, but we did not find Estonia in the public list of local numbers, and it may well turn out that the number has to be bought elsewhere while Apifonica serves as an outbound trunk. The company has changed both brand and legal entity twice in recent years (Apifonica → Dzinga → Apifonica again), so links to its documentation do not live long. Source: Apifonica — SIP Trunk — 09.09.2026.

Providers "under contract"#

For these operators the service either exists but the parameters are handed over only after a contract, or it is not publicly confirmed at all — so there can be no "what to enter" table here. Ask for the parameters using the list in "What to ask the provider" — all six fields of our form plus the format of the number in the call invitation — and always spell out the main point: the PBX sits in the cloud, not on the venue's premises, and it needs a trunk over ordinary internet to a public static address.

• CSC Telecom Estonia (csc.ee). The Estonian legal entity of the Baltic CSC Telecom group; the product is described plainly: "connect your office telephone exchange to the public telephone network over SIP, using either your existing internet connection or a dedicated data channel". The prices are public: €3.90 per month for one simultaneous call and two local numbers, a €50 connection fee (free with a two-year contract), a minimum of five lines, €3.90 for each extra call and €5 per month for ten extra numbers. Local and foreign numbers, 800/900 and short numbers are sold alongside. ⚠️ Neither the server address, nor the ports, nor the codecs, nor the authorisation mode appear in public materials — ask in writing. ⚠️ The number of simultaneous connections is contradictory in the marketing: the Estonian page promises "unlimited", the English-language storefront says "up to 100"; pin the figure down in the contract. Contacts: klienditugi@csc.ee, +372 610 9099.
• Tele2 Eesti. Publicly there are only the office telephony packages "Kontoritelefon 100" (€3 per month) and "Kontoritelefon 250" (€5 per month) excluding VAT, with 100 or 250 minutes and a promise that VoIP works "on a computer, a desk phone, a fax and a mobile". Not a single SIP parameter and not a word about connecting a third-party exchange. ⚠️ Formally the service is an account per device, and our PBX is just such a device for it, but there is no confirmation from the operator. Ask directly whether the SIP account of a number may be registered in your own office exchange running Asterisk — and ask for the parameters in writing. Bear in mind that Tele2's mobile line-up is strong and the account manager will offer a mobile solution by default.
• Elisa Eesti — not suitable. Both public "PBX services" are Elisa's own cloud exchanges: IP Centrex ("a virtual exchange, so that you do not have to acquire a telephone exchange of your own"; computer phone €2.556 per month, system phone €4.793, with recording €10.86, the call-centre package and the voice menu €26.84 each) and Elisa Ring — exchange features on top of mobile numbers. Your own PBX is redundant in such a scheme, and our features (point of sale, live call prompts, recording and call analysis) are unavailable there. The absence of a public page does not prove that a closed corporate offer does not exist: a written request to the business channel is worth making, and if the answer is no — port the number to someone who does offer a trunk.
• STV — not suitable. A cable operator in Tallinn and Narva: internet, TV and ordinary telephony on its own network, with call forwarding and caller ID display/withholding as the extras. There is no "SIP trunk to your PBX" product. An STV number is worth porting to an operator that has a trunk.
• Telegrupp AS — not an operator but a contractor. A systems integrator: it installs exchanges inside the customer's own perimeter and professionally wires external connections of various operators into them, including foreign and mobile numbers, with route selection. It sells no numbers or trunks of its own. It works as a contractor for "connect the Telia trunk to our PBX", but remember that it has an exchange of its own and an interest in selling it.

International providers with Estonian numbers#

Estonian numbers are sold by DIDWW, Zadarma and Twilio; for a foreign owner this is often the fastest route.

• DIDWW — Estonian numbers are available, but as "national" rather than "local": the coverage lists +372 numbers starting with 60, 62, 63, 64, 68, 69, plus mobile, toll-free and international toll-free ones. Two-way trunking, emergency call routing and number porting are supported; authorisation works both by password and by IP, that is, in both of our modes. National, mobile and international toll-free numbers require subscriber registration, plain toll-free ones do not.
• Zadarma — national Tallinn numbers +372 6… are in the public price list. Paperwork: a copy of the company registration certificate, a letter requesting the number and the actual address. ⚠️ One line per number — a single simultaneous call; a venue with a call queue will have to buy more. The number automatically becomes the caller ID of outbound calls from that account.
• Twilio — no Estonian geographic numbers. Its regulatory requirements list only mobile +3725 and toll-free +372800 numbers. The subscriber's address may be anywhere in the world, a company needs a trade register extract and an individual a document bearing their name. An Estonian landline number will have to come from elsewhere — this is a common planning mistake of "let us take Twilio for every country".
• Other aggregators (Telnyx, Plivo, CommPeak, AVOXI, Hivoox, FlyNumber, AstraQom) advertise Estonian numbers, but check the actual inventory and the regulatory terms by searching for a number in the portal before paying.

The parameters and modes of international providers are already described in the catalogue when adding a provider — the server address and the mode are filled in automatically, there is no need to copy them from a country page. Common to all of them: you may only present your own number outbound, and access to emergency numbers is either a separate service or not available at all.

Number porting#

• The right is written into the law. A customer may keep a number of the Estonian numbering plan when changing operator and when moving the point of service.
• What cannot be ported: the right does not cover a "fixed ↔ mobile" swap — a fixed number cannot be moved into a mobile service or the other way round. It does not apply to contracts concluded without identifying the customer either.
• Who pays. The porting fee must be cost-based and is paid by the new operator, the one you sign a contract with on the condition that the number is kept; for the subscriber porting is normally free.
• Porting is always initiated by the new operator on your application. According to the regulator, 75,444 numbers were ported in 2024, 3,690 of them fixed; shortening the operator-change window from four days to one is under discussion. Ask the receiving operator for the exact deadlines and the application form.
• ⚠️ The number belongs to the operator, not to you: when the contract is closed it goes back to the operator, who may not hand it to another customer for at least six months. For a venue whose number is printed on the sign and in maps, porting is the only way to keep it: port first, terminate the old contract afterwards, not the other way round.
• At cable operators the number is tied to the physical connection — there the order "port first, disconnect the internet afterwards" matters especially, otherwise the number is lost.

Rules and paperwork#

If it does not work#

1. Telia ViPÜ: registration is up, inbound calls arrive, outbound ones are rejected. This is the signature symptom of a missing P-Preferred-Identity header, which Telia requires in every outbound invitation. The PBX does not send it by default — the header is enabled on the server side, write to support.
2. Telia ViPÜ: you are registered, but outbound calls still do not go through. Check whether the static IP of your PBX is entered in Telia's service portal: the address check is on by default and it hits outbound calls specifically. Moving the exchange has the same effect — after the address changes, the record in the portal has to be updated.
3. Telia ViPÜ: busy on the third simultaneous call. The "ViPÜ number" profile has a hard cap of three simultaneous calls per number. A venue with a call queue needs the "kanal + DDI" profile, where the number of calls equals the number of channels paid for.
4. Two mobile numbers on one trunk ring at the same place. The seven-digit tails of the eight-digit mobile numbers have collided (see "Numbers in Estonia"). Split the numbers across separate trunks or give up per-number routing on this trunk.
5. The operator offers G.729 only. Our PBX speaks G.711 A-law, G.711 µ-law and G.722; with G.729 alone there will be no audio. With Telia this is not an issue — there G.711 A-law is the mandatory codec — but with Telia's second product and with the "under contract" operators the codec has to be agreed explicitly.
6. The provider requires an encrypted connection. Encryption is not supported for trunks — ask for an ordinary connection over UDP or TCP; with Estonian operators that is the main option anyway.
7. The operator's manager offers a cloud exchange instead of a trunk. The usual case with Elisa and Tele2. Phrase the request unambiguously: "a SIP trunk to our own exchange, which sits in the cloud on a public static address" — and if the answer is no, take the number from Telia, CSC Telecom or an international provider.

The common causes — a wrong login, a disabled line, closed ports — are covered in "If calls do not go through".

Frequently asked questions#

Do I need an Estonian company to get a number?#

There is no such requirement in the law: a number is issued under a communications contract, which requires identifying the person. In practice Estonian operators work with a local legal entity, and none of the ones we checked publishes a procedure for a foreign company to buy an Estonian number. If you have no company in Estonia, it is easier to take a +372 number from an international provider — their document requirements are spelled out in advance.

Which provider should I choose to get connected quickly?#

If you specifically need an Estonian operator — Telia ViPÜ: it is the only trunk in the country with fully published parameters and a clear price, but write to support about the P-Preferred-Identity header before your first outbound call. If you would rather not wait for a contract — DIDWW or Zadarma: a +372 number arrives in a day or two and their parameters are already in the provider catalogue.

Can I put an Estonian landline and mobile number on the same trunk?#

Landline numbers — yes, they are seven digits long and their tails do not overlap. Be careful with mobile ones: eight-digit numbers differ exactly in the first digit, which falls outside the match, so the PBX cannot tell two such numbers apart. If you need different routing, use a separate trunk per number.

Will an ordinary VoIP account do instead of a trunk?#

Yes, and in Estonia this is a common option: Telia's second product is built exactly that way — a SIP account per number. The downside is that ten numbers turn into ten trunks with separate passwords; the upside is that it is simpler to set up than a trunk with a range.

Why can I not present the head office number from another country on outbound calls?#

Under the Estonian numbering plan an operator may replace the calling number only with another number of the same subscriber issued by the same operator. On top of that, operators filter calls bearing Estonian numbers that arrive from abroad. Present outbound only the number that this same provider issued to you.

Sources#

Providers

• Telia Eesti — Vahendusjaama IP ühendus, parameters and prices: https://www.telia.ee/ari/kontor/kontori-telefon/vahendusjaama-ip-uhendus/
• Telia Eesti — service terms ET.05.PX.01.G "Vahendusjaama IP ühendus" (PDF): https://www.telia.ee/images/documents/tt/est/tt_ip_vahendusjaama_yhendus.pdf
• Telia Eesti — "Internetikõneteenuste kasutamise tingimused ja parameetrid" (PDF): https://www.telia.ee/images/documents/lepingud/lepingud-ja-tingimused/internetikoneteenuste_kasutamise_tingimused_parameetrid.pdf
• Telia Eesti — service terms ET.05.IN.64.G2 "Ärilahendus VoIP" (PDF): https://www.telia.ee/images/documents/tt/est/tt_arilahendus_voip.pdf
• CSC Telecom Estonia — SIP-Trunk: https://csc.ee/et/service/sip-trunk/
• Apifonica — SIP Trunk: PBX requirements and modes: https://www.apifonica.com/en/products/sip-trunk-and-numbers/
• Apifonica — business transfer to the Estonian SmartTel Plus OÜ: https://www.apifonica.com/en/blog/apifonica-business-transfer-notice/
• Tele2 Eesti — VoIP telefoniteenus: https://tele2.ee/ettevotja/teenused/koneteenused/voip
• Elisa Eesti — IP Centrex, prices: https://www.elisa.ee/et/elisast/teenuste-tingimused-ja-hinnakiri/ariklient/ip-centrex
• Elisa Eesti — Elisa Ring, service description: https://www.elisa.ee/et/elisast/teenuste-tingimused-ja-hinnakiri/ariklient/elisa-ring-teenuskirjeldus
• Telegrupp AS — VoIP ja IPCall: https://www.telegrupp.ee/sidelahendused/voip/
• STV — Telefon ärikliendile: https://stv.ee/ariklient/telefon

The regulator and numbering

• Elektroonilise side seadus (notice of activity, numbering permits, access to 112, number porting, caller ID display and withholding): https://estlex.ee/oigusakt/elektroonilise-side-seadus
• Eesti numeratsiooniplaan (closed plan, code 372, number types, dialling, caller ID substitution): https://estlex.ee/oigusakt/eesti-numeratsiooniplaan
• TTJA — Side aastaraamat 2024: numbering resources, number porting, the fight against spoofing (PDF): https://ttja.ee/sites/default/files/documents/2025-04/Side%20aastaraamat%202024.pdf
• TTJA — requirements for providing communications services: https://ttja.ee/ariklient/ettevotlus/nouded-sideteenuse-osutamisele

International providers

• DIDWW — Estonian national numbers: https://www.didww.com/phone-numbers/all-phone-numbers/Estonia/National
• DIDWW — regulatory requirements for Estonia: https://www.didww.com/resources/regulatory-requirements/Estonia
• Zadarma — Estonian virtual numbers: https://zadarma.com/en/tariffs/numbers/estonia/
• Twilio — regulatory guidelines for Estonian numbers: https://www.twilio.com/en-us/guidelines/ee/regulatory

All links were checked on 9 September 2026.

Related pages#

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