ONSIM Landline Replacement

Keep your landline working when the PSTN network switches off. Simple setup, reliable calls without broadband or VoIP!
The perfect alternative to BT Digital Voice

We will email you when the service launches. No spam.

Keep Your Phone. Replace the Line.

ONSIM Landline Replacement lets you keep the phone and number and handset you already own while replacing the old copper line that's being shut-off. Simple setup and dependable calling without installing broadband or new cables.

Keep Your Phone

Keep using the home phone you already know and trust. No need to replace it.

Simple Setup

Just unplug your phone from your old BT socket and plug it into the ONSIM Landline Replacement box

Keep Your Number

Family and friends keep calling the same number you have now - our helpful team manage the switch

Reliable Calling

Clear, dependable calls using the ONSIM Mobile network rather than unreliable VoIP.

6,500+

Customers

Landline Replacement Pricing

Two simple options

buy device

Lower monthly, no contract

£ 10

per month

£79 one-off for Landline Replacement box
Unlimited UK calls included
Use with alarms, lifts & analogue phones
Port your existing number included
Cancel anytime – no contract

Launching soon

popular

device included

£0 upfront – best value

£ 18

per month

Landline Replacement box included
Unlimited UK calls included
Use with alarms, lifts & analogue phones
Port your existing number included
24-month agreement

Launching soon

Want to speak to our sales team? Call us now on +443338804008

All prices shown are ex VAT

**UK Mins are outbound calls to major (O2, Vodafone, EE and Three) UK mobiles (07), landlines (starting 01, 02, 03) and freephone numbers (0800, 0808). Unlimited call and SMS allowances are subject to our fair usage policy (5,000 mins and 1,000 SMS). Usage outside of these allowances are charged at 5p/min & 5p/sms. By default we only allow calling to inclusive numbers (excluding non-standard 07 numbers) to avoid incurring additional charges. You can request that these restrictions are removed at our sole discretion.

FAQs

Frequently Asked Questions

Everything you need to know about keeping your home phone working.

Will my phone still work?

Yes. You keep your current home phone and it works just like before.

Can I keep my number?

Yes. Your landline number can stay the same so no one has to learn a new number.

Do I need broadband?

No. Calls use the ONSIM Landline SIM on the mobile network.

Is it hard to set up?

No. We keep it simple and can guide you through the steps.

Will it sound the same?

Call quality is clear and reliable, just like a normal landline.

Who is it for?

Anyone who wants to keep a familiar home phone when the old landline network switches off.

Keep Your Home Phone Working

Simple setup, friendly support, and the same number you already use.

Coming Soon

Learn more about landline replacement and home phone options

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Explore the ONSIM blog for practical guides on call handling, keeping personal numbers private, WiFi Calling, roaming, and more.

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