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.
ONSIM Landline Replacement lets you keep the 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 using the home phone you already know and trust. No need to replace it.
Just unplug your phone from your old BT socket and plug it into the ONSIM Landline Replacement box
Family and friends keep calling the same number you have now - our helpful team manage the switch
Clear, dependable calls using the ONSIM Mobile network rather than unreliable VoIP.
Customers
Two simple options
Lower monthly, 30 day rolling contract
£0 upfront – best value
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
Everything you need to know about keeping your home phone working.
Yes. You keep your current home phone and it works just like before.
Yes. Your landline number can stay the same so no one has to learn a new number.
No. Calls use the ONSIM Landline SIM on the mobile network.
No. We keep it simple and can guide you through the steps.
Call quality is clear and reliable, just like a normal landline.
Anyone who wants to keep a familiar home phone when the old landline network switches off.
Simple setup, friendly support, and the same number you already use.
Explore the ONSIM blog for practical guides on call handling, keeping personal numbers private, WiFi Calling, roaming, and more.
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