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 free seat tier (1 user, 1 UK DDI, 30 minutes/month) and Pay-as-you-go from £0/month + £0.02 per UK landline minute, with no contract. Paid plans start at £6.95/user/month and come with a 30-day free trial.

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 Plus and above, typically within 24 hours.

Can I keep my existing phone number?

Yes — Silux Call offers free UK number porting on Plus and above, 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.

Microsoft Teams Direct Routing setup with a UK SBC

Step-by-step PowerShell wiring for Teams Direct Routing on a UK SBC, including caller-ID assignment and emergency calling.

Microsoft Teams Phone with Calling Plan is convenient, expensive, and locks you to Microsoft's PSTN rates. Direct Routing lets you keep Teams as the user interface and bring your own carrier (us). Per-minute cost drops 60-80%.

What Direct Routing is

Direct Routing is the official Microsoft mechanism to pair a third-party SBC (Session Border Controller) with Teams Phone. The Teams client still rings and dials as before; the actual call traverses your chosen carrier instead of Microsoft's PSTN backbone.

Prerequisites

Microsoft 365 Business Standard or higher with a Teams Phone licence per user.
A Silux Call Pro or Enterprise tenant (Direct Routing is feature-gated on Pro+).
A globally-resolvable FQDN that points to our SBC — we ship sbc.siluxcall.co.uk for shared use; enterprise tenants get their own.
Teams admin (Global Admin or Teams Service Admin) on the Microsoft 365 side.

The setup, end-to-end

In Silux Call dashboard → Microsoft Teams, click Onboard. Enter your SBC FQDN (we suggest sbc.siluxcall.co.uk) and the caller-ID number to attach to the first user.
We mint a 24-character trunk secret and generate the PowerShell snippet your Teams admin needs to run.
Open Teams PowerShell as Global Admin: Connect-MicrosoftTeams
Paste the snippet. It registers the SBC, creates a voice route, assigns a PSTN usage, and binds it to a voice routing policy.
Run Grant-CsOnlineVoiceRoutingPolicy for each user that should use Silux Call as their phone provider.
Assign a phone number with Set-CsPhoneNumberAssignment -PhoneNumberType DirectRouting.

Emergency calling (UK)

Ofcom requires that every UK Direct Routing user can dial 999. We auto-configure an emergency policy that pinpoints the call to the user's registered London office address. For multi-site tenants, set per-site emergency locations through the Teams admin centre.

How much does it save?

Provider	UK landline /min	UK mobile /min
Microsoft Domestic Calling Plan	included up to 1,200 min/user; £0.06+ over	included up to 1,200 min/user; £0.11+ over
Silux Call Direct Routing	£0.02	£0.05

For a 50-user finance firm averaging 200 minutes/user/day, the saving is typically £24,000-£40,000 per year.

Caveats

Teams supports a subset of SIP; some advanced features (call park, hot-desking) don't survive the Teams client. We retain them in the Silux Call dashboard for users who want both.
Operator Connect is Microsoft's newer (2022+) drop-in alternative. We're certifying for it; expect availability Q3 2026.