Can my business just use mobiles after the switch-off?

The short answer: yes, but read the catches

There's no law that says a business must keep a phone line. When the analogue network switches off on 31 January 2027, you're free to drop the landline entirely and run on mobiles if that suits how you work.

For some businesses that's genuinely the right call. For others it quietly breaks things. The decision comes down to three questions: your number, your kit, and your coverage.

Catch 1: your number

This is the big one. An 01 or 02 landline number can't live on an ordinary mobile SIM — mobiles use 07 numbers. So if customers know you by your landline number, going mobile-only means either:

• Losing the number (and re-printing every sign, card and listing), or
• Porting it to a VoIP service — a Digital Voice line — which can then ring through to an app on your mobile.

That second option is usually the answer, and it's the point most "just use mobiles" advice skips: to keep the number and use it on your phone, you need a digital line behind it, not a SIM. If keeping one number cheaply is your real goal, see keeping one phone number for a club or village hall cheaply.

Catch 2: what else is on the line

A mobile only does voice and text. A business line often quietly carries more:

• A card payment machine on an old phone socket.
• A door-entry intercom.
• An alarm that dials out to a monitoring centre.
• A fax (still real in some trades).

Mobiles don't replace any of those. Go mobile-only and each one needs its own separate fix — often more hassle and cost than simply keeping one cheap digital line.

Catch 3: coverage

Mobiles live and die on signal. Back offices, basements and rural sites can be patchy, and a dropped business call costs you. A digital phone line runs over your broadband instead, so calls stay steady as long as the internet's up. If your premises have weak mobile coverage, test it honestly before betting the business on it.

Mobile-only vs a digital line

	Mobile-only	Digital phone line (VoIP)
Keep your 01/02 number	No (not on a SIM)	Yes
Card machine / alarm / intercom	Needs separate fixes	Can stay on the line
Depends on	Mobile signal	Broadband
Best for	Solo / fully-mobile businesses	Most settled small businesses

Who should go mobile-only

It's a fair choice if you're a solo or micro business that already runs on a mobile — a tradesperson, a consultant — with no landline number worth keeping, no card machine, and nothing dialling out on a line. Let the analogue line go and you're done.

For most small businesses with a known number and kit on the line, a digital phone line is the smoother answer: it keeps the number, keeps the devices working, and costs only a few pounds a month per user. Mobile-only sounds simplest, but the number is usually what makes it more complicated than it looks.