Built on Simwood

The carrier under the next generation.

Voice is being consumed by software now: AI agents, contact-centre platforms, communications APIs, products with voice built in. All of them live or die on the carrier underneath - and most are currently paying a middleman for ours. We're a Tier-1 UK voice carrier with direct PSTN interconnect. Build on the real thing.

AI Voice buildersYour agent is only as good as the network under it: one that drops calls or adds latency isn't a product. Direct SIP to the PSTN, clean numbering, STIR/SHAKEN, high concurrency and UK data residency - without a CPaaS margin between you and the carrier. And if you want a head start, our Conversational AI primitives and in-call intelligence are already built.
CCaaS platformsThe carrier layer under your platform: compliant UK and EU voice interconnect, call recording done properly, and the data residency your banking, insurance and healthcare customers will audit you on. Omnichannel through WhatsApp Business and Teams. Your platform out front, our network underneath.
CPaaS providersThis one's a partnership, not a product sale: add us as your preferred UK carrier. Wholesale origination and termination, DID inventory, automated porting and fraud prevention at volume, with the quality and economics only direct interconnect delivers.
SaaS with communications insideClick-to-call in your CRM, appointment reminders in your booking flow, voice built into your lettings platform. Embed voice, messaging, WhatsApp and AI through one API without becoming a telecoms company - direct carrier pricing, UK-first support, UK data handling.
Carriers & resellersThe customers we grew up with, and still the foundation. Everything above is also how we help you modernise: programmable everything, WhatsApp, Conversational AI - your portfolio moves forward without you having to build it.

Direct PSTN interconnect · all four UK mobile networks · Ofcom-regulated · UK data residency · 100% SLA, last outage 2018 · ~150ms AI voice TTFB

FAQ

Questions, answered.

Who builds on Simwood?

AI voice builders, CCaaS platforms, CPaaS providers, SaaS products with communications inside, and carriers and resellers.

Why build on Simwood instead of a CPaaS?

Simwood is a Tier-1 UK voice carrier with direct PSTN interconnect, so you get direct SIP to the PSTN, clean numbering, STIR/SHAKEN, high concurrency and UK data residency without a CPaaS middleman's margin between you and the carrier.

Is Simwood suitable for regulated sectors?

Yes. Compliant UK and EU voice interconnect, call recording done properly and UK data residency that banking, insurance and healthcare customers audit for.

Do I have to become a telecoms company to embed voice?

No. You can embed voice, messaging, WhatsApp and AI through one API at direct carrier pricing, with UK-first support and UK data handling.

Where do I find the API?

Simwood has been API-first since 1996. See the Simwood API overview at simwood.com/api/ and full documentation at docs.simwood.com.

The strategy, out loud

We're building for a future where carriers don't exist.

We're the only carrier willing to sacrifice core carrier revenue to get there first - yesterday's revenue traded for tomorrow's market share. Build on us and do the same.

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