7726: the free number that reports spam texts and scam calls
Forward a scam text to 7726, free on every UK network, and your provider can trace and block the sender. Here is exactly how the reporting service works.
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 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.
7,500+
Customers
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Important: this is a voice line, not an alarm line
ONSIM Landline Replacement is for making and receiving voice calls. It is not suitable for, and must not be used with, telecare or social alarm equipment, personal or pendant alarms, warden call systems, monitored intruder or fire alarm diallers, lift emergency telephones, or any other equipment that automatically dials an alarm receiving centre. We have not tested this service with such equipment and do not support it.
This is not unique to us. Analogue alarm and telecare equipment signals by sending tones down the line, and those tones are unreliable over any digital or mobile voice path. The failures are also silent, so the equipment appears to be working right up until it is needed. The fix is not a different phone line, it is different signalling.
Landline Replacement Pricing
Two simple options. Prices include VAT.
buy the device
Pay for the box once, lowest monthly
£ 12
per month inc VAT- £115.20 inc VAT one-off for the box
- Unlimited UK calls included
- Use your existing analogue handset
- Port your existing number included
- 30 day rolling contract, cancel any time
popular
spread the device
Nothing to pay today, then it drops to £12
£ 21.60
per month inc VAT, for 12 months- Nothing to pay upfront
- £9.60 a month for the box, for 12 months only
- Drops to £12 a month after that
- Same £115.20 for the box, no interest, no fees
- Unlimited UK calls, porting included
Want to speak to our sales team? Call us now on +443338804008
Prices above include VAT. Ex VAT that is £96 for the box and £10 a month, or £18 a month for 12 months then £10 a month.
**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.
What does it cost, and what is the difference between the two plans?
The box costs £115.20 including VAT and the service is £12 a month including VAT, with unlimited UK calls. You can either pay the £115.20 up front, or spread it at £9.60 a month for 12 months on top of the £12 service, so £21.60 a month for the first year. After 12 months the box instalment ends and you pay £12 a month. Either way the box costs the same £115.20. We do not add interest, and there are no setup, admin or late payment fees on the spread option. Ex VAT those figures are £96 for the box, £10 a month for the service, and £18 a month for the first 12 months.
Does the price go up during the 12 months?
No. If you spread the cost of the box, your price is fixed at £21.60 a month including VAT for the whole 12 months. We do not apply mid-contract price increases to it. At the end of the 12 months your bill goes down to £12 a month, not up.
Do I own the box?
Yes, from day one, on both plans. Spreading the cost does not mean renting it. If you leave part-way through the 12 months, the remaining device instalments become payable, because you keep the box.
Can I use it with a telecare alarm, pendant or care line?
No. ONSIM Landline Replacement is for voice calls and must not be used with telecare or social alarm equipment, personal or pendant alarms, or warden call systems. This is an industry-wide issue rather than something specific to us: analogue telecare signals by sending tones down the line, and those tones are unreliable over any digital or mobile voice path. Worse, the failures are silent, so the equipment looks fine until the moment it is needed. If you or someone in your household uses telecare, speak to your telecare provider or your council about a digital alarm unit that signals over its own mobile connection.
Can I use it with a burglar alarm or fire alarm dialler?
No. We have not tested this service with alarm diallers and do not support it for that purpose. Monitored alarm signalling has to meet transmission time, availability and supervision requirements that a voice path cannot evidence, and an unsupervised line only reveals it is dead when the panel tries to use it. Ask your alarm installer to fit a digital or mobile signalling module, which is the route the industry is taking anyway.
Can I use it for a lift emergency phone?
No. Lift emergency phones fall under BS EN 81-28, which requires the system to alert if the communication link fails and to support periodic automatic test calls. That cannot be delivered over a standard analogue port. Your lift maintenance contractor can specify a compliant GSM or 4G lift phone solution.
What about 999 calls?
Emergency calls work as normal and are free. Your registered installation address is held against your number, so the emergency operator sees where you are. The box also has a built-in battery, so it keeps working through a power cut, though you will need a corded analogue handset rather than a cordless one, because a cordless base station needs mains power of its own.
Keep Your Home Phone Working
Simple setup, friendly support, and the same number you already use.
Learn more about landline replacement and home phone options
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7,500+
Customers
4.53m
Monthly Calls
12
Years of Service
39
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