When does the UK PSTN switch off?

BT Openreach is retiring the UK PSTN (WLR 2) on 31 January 2027. Every UK business landline must move to a digital service such as VoIP or full-fibre voice before that date.

What is the cheapest UK business VoIP?

Silux Call offers a 14-day free trial (1 user, 1 UK number, 30 minutes) with no card required. Paid plans start at £4.75 per LINE per month — not per user — with no contract.

Does Silux Call have a free trial, and do I need a credit card?

Yes. Every paid plan comes with a 30-day free trial and no credit card is required to start — most UK rivals offer only a 7 or 14-day trial, and several require a card up front. You can also stay on a permanently free seat with no card at all. Signing up takes about 60 seconds.

How quickly can I get a UK virtual landline number?

You can sign up in about 60 seconds and choose a UK virtual landline number (020, 0161, 03 or 0800) instantly — no engineer visit, no hardware and no contract. Existing numbers port across free on every plan, typically within 24 hours.

Can I keep my existing phone number?

Yes — Silux Call offers free UK number porting on every plan, typically completing in 24 hours. We support PAC and STAC porting workflows.

Does Silux Call work with Microsoft Teams?

Yes — Silux Call supports Microsoft Teams Direct Routing on the Pro tier, including a self-service onboarding wizard that issues the PowerShell snippet for your Teams admin.

Is Silux Call GDPR and HIPAA compliant?

Silux Call ships UK GDPR-compliant call recording with two-party consent flows, plus one-click HIPAA enrolment that locks 6-year retention, KMS-backed encryption, and PCI DTMF redaction. A one-click compliance report exports an auditor-ready PDF.

How does Silux Call block scam calls?

Silux Call screens every inbound call with an AI scam shield in under 0.5 seconds. Known HMRC, parcel, and account-spoof patterns are blocked before your phone rings — a feature no other UK business VoIP provider ships.

Silux Call vs Gamma Horizon: which UK business phone system wins in 2026?

Looking for a Gamma Horizon alternative? Silux Call and Gamma Horizon are both UK wholesale UCaaS. The short answer: Silux Call wins for UK SMBs on price, bundled AI, and PSTN-switch-off readiness, while Gamma Horizon (channel / quote-only) is a known quantity if you are already embedded in it. Reseller-only, no direct self-service, no free tier — below is the full, honest, GBP-priced breakdown for UK businesses.

Is Silux Call a better Gamma Horizon alternative?

Yes for most UK businesses: Silux Call bills in GBP with no contract, includes AI receptionist minutes and pre-ring scam-call screening the headline Gamma Horizon plan does not, and offers a 14-day free trial with no card. Reseller-only, no direct self-service, no free tier.

Silux Call

From £4.50 a line · UK-domestic · GBP · no contract

14-day free trial (1 user, 1 DDI, 30 mins UK) — no card
Unlimited UK landline AND mobile calling from £8.95 a line
AI receptionist minutes included from £19.95 a line, not sold as a separate product
Pre-ring AI scam-call shield
Cross-tenant federation (free internal extension dialling)
Real-time call translation as live subtitles
One-click UK GDPR tooling reporter
Stripe-native reseller billing
White-label brandable mobile + desktop softphone
Microsoft Teams Direct Routing + SAML SSO

Gamma Horizon

channel / quote-only · UK wholesale UCaaS

Reseller-only, no direct self-service, no free tier
No pre-ring AI scam-call shield
No cross-tenant federation
No one-click UK GDPR compliance reporter
No Stripe-native end-customer billing
No AI receptionist included in the headline price

Pricing side-by-side (GBP)

Plan tier	Silux Call	Gamma Horizon
Free trial	14 days free, no card (1 user, 1 DDI)	Not offered
Entry paid plan	£4.50/line/month (Starter)	channel / quote-only
Unlimited UK landline & mobile	£8.95/line/month (Plus)	See their list price
AI receptionist	Minutes included from £19.95/line (Pro); unlimited add-on £199/mo	Add-on or unavailable
Contract	None	Often 12–36 months

Switching from Gamma Horizon

Audit — we generate a free PSTN switch-off and line-by-line Gamma Horizon audit (no card).
Port — free UK landline porting on every plan. Send a recent bill and a signed letter of authority and we handle the rest.
Re-route — copy your IVR, hunt groups and working hours via our import tool.
Run in parallel — keep both providers live for 7 days, then cut over.
Cancel Gamma Horizon — we provide the cancellation template.

Start 14-day free trial — no card Book a migration call

FAQs — Silux Call vs Gamma Horizon

Is Silux Call cheaper than Gamma Horizon?

Silux Call starts free for a 14-day trial, then £4.50 a line on Starter and £5.95 on Lite with 2,500 UK minutes. Unlimited UK landline AND mobile calling is £8.95 on Plus. Gamma Horizon list price: channel / quote-only. Silux Call bills in GBP on rolling monthly terms with no setup fee.

Can I migrate from Gamma Horizon to Silux Call?

Yes. We offer free UK landline porting on every plan — send us a recent bill and a signed letter of authority — plus a guided Gamma Horizon migration that imports your IVR, hunt groups and working hours. Your old line keeps working throughout the port.

What does Silux Call do that Gamma Horizon doesn't?

Reseller-only, no direct self-service, no free tier. Silux Call adds pre-ring AI scam-call screening, cross-tenant federation, a one-click UK GDPR tooling reporter, Stripe-native reseller billing, translated call transcripts, and a 14-day free trial.

Is Gamma Horizon or Silux Call better for the 2027 PSTN switch-off?

Both run over IP and survive the switch-off, but Silux Call ships a free per-line PSTN audit and a WLR2 migration plan with every account, which Gamma Horizon does not bundle.

Does Silux Call have a free trial versus Gamma Horizon?

Yes — 14 days, no card: one user, a UK landline from our trial pool and 30 outbound minutes. Paid plans do not carry a second trial of their own.