A Czech number for your voice agent
Voice agent platforms don't sell Czech or Slovak numbers, so you have to bring one. At volai you get a Czech number right away for €1.05 per 30 days and point it at your platform's SIP address.
Who this is for
Your agent is on ElevenLabs
Bring the number in as a SIP trunk. We have verified inbound and outbound calls live, step by step in the ElevenLabs guide.
Your agent is on Vapi
Bring the number in through a BYO SIP trunk, with no login details. We have verified inbound calls live, outbound not yet. The setup is in the Vapi guide.
Your agent is somewhere else
Retell, Bland or your own PBX: other platforms go through a generic SIP trunk, see the SIP documentation. We have verified the procedure for ElevenLabs and Vapi only, so make a test call on anything else. Synthflow accepts a number over SIP on its Enterprise plan only.
1Create an account and get €2 in credit
Sign up at volai.be. After you verify your e-mail, €2 lands on your account and you don't need to enter a card.
2Pick a number from the pool
In the portal (Numbers) or through the API, take a Czech number from any of the 14 regions or from the non-geographic 910 range, all the same way and without documents. It is yours right after you buy it and costs €1.05 per 30 days. A number at the address of your business premises is a separate option, and the Slovak number is a Bratislava +421 2 one only.
3Route the number to your platform's SIP address
Switch the number to SIP mode and set your platform's SIP address as the destination. The exact address format and the platform settings are in the ElevenLabs and Vapi guides.
curl -X PATCH "https://volai.cz/v1/numbers/+420601234567" \
-H "Authorization: Bearer vk_YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{"routing": {"mode": "sip", "sipUri": "sip:+420601234567@YOUR_PLATFORM_SIP_ADDRESS"}}'Ways to get a Czech number
ElevenLabs, Vapi, Retell, Bland and Synthflow don't sell Czech or Slovak numbers: you buy one from a carrier and the platform just accepts it. These are the ways we have checked. Each wants different documents and takes a different time.
| Way to get it | Documents and address | Wait | Number per month | Inbound minute | Fits when |
|---|---|---|---|---|---|
| volai | Documents and addressCzech number from any of the 14 regions or the 910 range: no documents, just an e-mail and a verification code; credit is topped up by card and the number is active right after purchase. A number at the address of your business premises is a separate option. | WaitRight after purchase | Number per month€1.05 / 30 days | Inbound minute€0.0209 | Fits whenYou want the number right away, without documents, on one account with a call history. |
| Twilio, national number +420 910 | Documents and addressNo documents, an address from any country. Voice only. | WaitNot verified | Number per month€1.44 (USD 1.50) | Inbound minute€0.0105 (USD 0.0107) | Fits whenYou can handle a second account and talk roughly 40 inbound minutes a month or more. |
| Twilio, geographic number | Documents and addressAn address in the number's area and a document proving it; a company needs a registry extract. | WaitDocument review, usually up to 3 business days | Number per month€1.44 (USD 1.50) | Inbound minute€0.0105 (USD 0.0107) | Fits whenYou have an address in the number's area and want a geographic number straight from Twilio. |
| Telnyx, geographic number | Documents and addressID, proof of address not older than 3 months, and being physically in the Czech Republic when you buy. | WaitNot verified for Czechia, generally days | Number per month€0.959 (USD 1) + €0.959 setup | Inbound minute€0.0059 (USD 0.006) | Fits whenYou are in the Czech Republic, have the documents and watch the minute price. |
| Zadarma, city number | Documents and addressAn address in the number's region; your details are verified before activation. | WaitAfter verification | Number per monthfrom about €1.67 (EUR 1.6), 6-month subscription | Inbound minuteFree per its price list, rate not verified | Fits whenYou have an address in the number's region and don't mind a six-month subscription. |
| peoplefone, Czech number | Documents and addressCommercial register extract, proof of address in the Czech Republic and ID of the signing person. | WaitOrder on request, answer within 24 hours | Number per monthCHF 10 | Inbound minuteNot verified | Fits whenYou are a company based in the Czech Republic. |
The data on the platforms and number providers comes from their public pages, checked on 16 Oct 2026. Prices exclude VAT, are converted at 23 CZK per USD and 25 CZK per EUR, and change; check with the provider before you order. "Not verified" means we could not find the figure.
Step-by-step guides
Frequently asked questions
- Can I receive SMS on this number?
- No. A voice number (landline or VoIP) doesn't receive SMS. Two kinds of numbers do. The mobile number add-on is a separate Czech number for SMS only at €12.09 per 30 days, receiving included. The calls and SMS number is a Prague landline at €2.05 per 30 days (the fee is charged only after activation, usually within 1 business day) that people can call and text, and that your agent places calls and sends SMS from. Calls on it, though, are answered only by an agent on volai's own voice engine: it cannot be routed to SIP or forwarded to another number, so an agent running at ElevenLabs or Vapi cannot answer calls on it and the number is not a fit for such an agent. We don't guarantee verification codes from services; the numbers are for texting with people. You can send SMS through the REST API (
POST /v1/messages) without them, at €0.0567 per segment, but the recipient can't reply. - Can I get a Slovak number too?
- Yes, a Bratislava +421 2 number at €1.05 per 30 days, paid three months ahead (€3.13). Stock is replenished by hand, so it may not be available right away.
- What if my platform asks for login details?
- For inbound calls neither ElevenLabs nor Vapi needs login details, just allow our IP range
81.31.45.0/24. The ElevenLabs outbound trunk does need your line's credentials; the steps are in the ElevenLabs guide and the SIP documentation. - How does my agent call out from the Czech number?
- Through a relay: right before the call you create a short-lived connection with
POST /v1/relayand give the platform thesipName. A minute costs €0.0384 with no agent surcharge; the steps are in the ElevenLabs guide. - Is volai the cheapest way to a Czech number?
- No, the easiest. Above roughly 40 inbound minutes a month Twilio comes out cheaper (€1.44 (USD 1.50) for the number and €0.0105 (USD 0.0107) a minute), but at volai you get a number right away and without documents.