Contact Centres
Virtual numbers & SIP for contact centres
When you run many numbers across many countries — and thousands of calls at once — the hard parts are scale, sizing and delivery. Temptera provisions numbers in 100+ countries, sizes the concurrency your floor actually needs, delivers calls to your platform however it prefers, and reroutes when something goes dark. From a carrier that operates the calls, not a reseller.
Numbers at scale
Many numbers, many countries — one estate
A contact centre rarely wants one number. You want a block of local numbers per market, so callers see a familiar dialling code and answer, plus toll-free lines for support and dedicated numbers per campaign or client. Temptera lets you build and manage that whole estate across 100+ countries from a single account, instead of stitching together a different vendor in every region.
- Local, national, mobile and toll-free number types, where supported in each country.
- Number blocks for per-market, per-campaign or per-client segmentation.
- Availability, number type and any registration requirements are shown at order — they vary by country.
- Bring existing numbers with you: port them in where portable, with no lock-in.
Coverage figures stay honest: we quote 100+ countries and confirm the exact availability for your list when you order, because number types and identity rules differ market to market.
Concurrency & channels
Sized by simultaneous calls, not by the number count
The figure that governs a contact centre is concurrency — how many calls are live at the same moment at your busy hour. That is what we provision channels for. The number of DIDs you own and the number of channels you run are two different things.
A campaign that dials heavily needs channels for its outbound peak; a support line needs channels for its inbound spikes; a blended floor needs both. We help you translate agent counts, dialler pacing and expected answer rates into a channel figure with sensible headroom, then let you flex it as seasons and campaigns move. Because channels are decoupled from your number blocks, you can hold thousands of numbers and still pay attention only to the concurrency you actually carry.
| Term | What it means | What drives it |
|---|---|---|
| Numbers (DIDs) | The addresses callers dial or that you present as caller ID. | Markets, campaigns and clients you segment by. |
| Channels | How many calls can be live at once across the trunk. | Your peak simultaneous calls, plus headroom. |
| Concurrency | The live-call count at your busiest moment. | Agents, dialler pacing and answer rates. |
How calls reach you
Delivered to your platform, your way
Inbound calls have to arrive somewhere. We hand them to your contact-centre platform over standard SIP in whichever of three ways suits your setup — and calls you originate go back out the same path with your chosen caller ID.
SIP URI
We send calls to the SIP address you nominate. The cleanest fit for cloud platforms and session border controllers that expect calls at a hostname.
IP allowlist
We peer with your SBC by address — no registration — and only authorised endpoints exchange calls. Suited to on-net platforms with a fixed edge.
PSTN forward
Not ready for SIP on a given route? We forward the number to an existing PSTN line while you migrate — and it doubles as a resilience fallback.
Works with your stack: SIP-capable platforms such as FreeSWITCH, Asterisk and 3CX connect the same standard way. Connection details are provisioned privately to your account — never published here. New to the delivery model? Read how DID numbers work with SIP trunking.
Failover & resilience
Calls keep arriving when something goes dark
A busy floor cannot afford a single point of failure on the inbound path. Because delivery is decoupled from the numbers, you can define more than one target for a route — a primary SIP URI or IP, and one or more secondaries in another data centre or region. If the first stops answering, calls reroute to the next healthy endpoint, and a PSTN forward can sit behind them as a last resort.
- Primary plus secondary delivery targets, so a route survives one endpoint dropping.
- Reroute to a healthy target when the first fails to answer, where your platform supports it.
- PSTN forward as a final fallback to keep a line reachable during an outage.
- We operate the call path and help you diagnose SIP faults when a route misbehaves.
Exact failover behaviour is designed with you and is subject to what your platform can signal — we set honest expectations rather than promising automatic magic.
Why Temptera
The numbering & delivery layer for high-volume floors
One estate, 100+ countries
Build and manage number blocks across markets from a single account, instead of a vendor per region.
Sized to your peak
Channels provisioned to the concurrency you carry at busy hour, with headroom you can flex.
Delivered your way
SIP URI, IP allowlist or PSTN forward — matched to whatever platform your floor already runs.
Resilient by design
Primary and secondary targets with a PSTN fallback, and a carrier that helps diagnose the SIP path.
Prefer to see it as trunking first? Read about SIP trunking and DID numbers, or check live rates on the pricing page.
FAQ
Contact centre numbers — answered
Running an AI-assisted floor as well? See phone numbers for AI voice agents and the guide on virtual numbers for AI voice agents.
How many numbers can a contact centre get, and in how many countries?
You can provision many numbers across 100+ countries — local, national, mobile and toll-free where supported. Availability and the number types offered vary by country and are shown at order, along with any per-country verification.
How do you size concurrency and channels for a call centre?
Concurrency is the number of simultaneous calls your operation carries at peak. We provision channels to cover that peak with headroom, and you can scale channels up or down as campaigns and seasons change. Sizing is agreed with you rather than fixed to a number of DIDs.
How are calls delivered to my contact centre platform?
Three standard ways, chosen to match your platform: a SIP URI we send calls to, an IP allowlist that peers your session border controller by address, or a PSTN forward to an existing number. It works with SIP-capable platforms on your side such as FreeSWITCH, Asterisk or 3CX.
What happens if my platform or a data centre goes down?
You can define more than one delivery target — a primary and one or more secondaries — so calls reroute to a healthy endpoint if the first stops answering. A PSTN forward can act as a last-resort fallback. Failover behaviour is configured with you and is subject to what your platform supports.
Can I keep my existing numbers when moving to Temptera?
Yes, where the numbers are portable. We confirm portability per country before anything is scheduled, and there is no lock-in — the numbers remain yours and can be ported out later.
Scale your contact centre's numbering
Tell us the markets you cover, the platform your floor runs on and your busy-hour concurrency — we'll confirm coverage, size the channels and set up delivery with failover. No lock-in.