Divert Landline Calls to Mobile UK: Codes for BT, Sky, Virgin & VoIP
Quick answer: Pick up your landline and dial *21*[mobile number]# to divert all calls to your mobile. This universal code works on BT, Sky, TalkTalk, and most other UK landline providers. For Virgin Media, you'll need to dial *21*0[mobile number]# (note the extra zero). To cancel, dial #21#. Below, we cover every provider's codes, costs, and a smarter alternative for businesses.
What Are the Call Divert Codes for Each UK Landline Provider?
Call divert codes vary slightly between providers. Here's a complete reference table with codes for diverting all calls, diverting unanswered calls, and cancelling diversions:
| Provider | Divert All Calls | Divert Unanswered Only | Cancel Divert | Cost |
|---|---|---|---|---|
| BT | *21*[mobile]# | *61*[mobile]# | #21# or #61# | ~3.5p–10p/min to mobiles |
| Sky | *21*[mobile]# | *61*[mobile]# | #21# or #61# | Included in call plans / per-min otherwise |
| Virgin Media | *21*0[mobile]# | *61*0[mobile]# | #21# or #61# | ~10.5p/min to mobiles |
| TalkTalk | *21*[mobile]# | *61*[mobile]# | #21# or #61# | Per-min charges apply |
| VoIP / Hosted PBX | Set in online portal or app | Set in online portal or app | Toggle off in portal | Usually free (included) |
Important: Virgin Media requires an extra 0 before the mobile number. For example, to divert to 07700 900123, you'd dial *21*007700900123# on a Virgin line, versus *21*07700900123# on BT, Sky, or TalkTalk.
How Do I Divert My Landline to My Mobile Step by Step?
Follow these steps to activate call forwarding on a standard UK landline (BT, Sky, or TalkTalk):
- Pick up your landline handset and wait for a dial tone.
- Dial *21* followed by your full mobile number including the leading 0 (e.g., *21*07700900123).
- Press # to confirm. The full sequence looks like:
*21*07700900123# - Listen for a confirmation tone — typically a stutter or a series of beeps indicating the divert is active.
- Test it: Call your landline number from another phone to confirm calls are forwarded to your mobile.
To divert only unanswered calls (your landline rings first, then forwards after approximately 15–20 seconds), replace *21* with *61* in step 2.
To cancel the divert, pick up the handset and dial #21# (for all-call diverts) or #61# (for unanswered-call diverts).
How Much Does Landline Call Diversion Cost in the UK?
This is where many businesses get caught out. Diverted calls are not free. When you forward a landline call to a mobile, your provider charges you for the landline-to-mobile leg of the call — even though the caller dialled a landline number.
Typical costs in 2024–2025:
- BT: Approximately 3.5p–10p per minute to UK mobiles, depending on your calling plan.
- Virgin Media: Around 10.5p per minute to UK mobiles.
- Sky / TalkTalk: Varies by plan — often included in unlimited call bundles, but check your terms as diversions may be excluded.
For a small business receiving 30–50 diverted calls per day, this can quietly add £50–£150+ per month to your phone bill. The charges are rarely visible until your bill arrives.
We recommend checking with your provider whether diverted calls are counted as part of any inclusive minutes bundle, as many plans exclude call forwarding from their allowances.
Is There a Better Alternative to Call Diversion for Businesses?
Yes. If you're regularly diverting landline calls to a mobile, you're paying for a workaround when you could use a proper solution. A VoIP (Voice over IP) or hosted phone system eliminates the need for call diversion entirely — because your business calls ring directly on your mobile, laptop, or desk phone over the internet.
Here's how VoIP compares to traditional call diversion:
| Feature | Landline + Call Divert | VoIP / Hosted Phone System |
|---|---|---|
| Calls ring on mobile | ✅ (via divert) | ✅ (natively via app) |
| Per-minute divert charges | ❌ Yes — 3.5p–10.5p/min | ✅ None — calls included |
| Caller sees your business number | ✅ They dial the landline | ✅ Full control of outbound CLI |
| Call on mobile AND desk phone | ❌ One or the other | ✅ Simultaneous ring on all devices |
| Auto-attendant / call menus | ❌ Not available | ✅ Included |
| Time-based routing (e.g., out of hours) | ❌ Manual toggle | ✅ Automatic schedules |
| Keep your existing number | ✅ | ✅ Port it across for free |
| Typical monthly cost | £15–£30 line rental + divert charges | From £6–£12 per user/month |
Best for small businesses: A hosted VoIP system from a specialist provider like Connection Technologies. You keep your existing landline number, pay less per month, and never need to remember divert codes again. Calls ring on your mobile app, desk phone, and laptop simultaneously — and you can manage everything from an online portal.
What About the BT Digital Switchover (PSTN Switch-Off)?
It's worth noting that BT's traditional copper landline network (the PSTN) is being switched off by January 2027. After that date, all UK phone lines will run over a digital or VoIP connection. If you're currently using an analogue landline with star-code call diversion, you'll need to move to a digital solution eventually.
Moving to VoIP now means you avoid the last-minute rush, keep your number, and start saving on divert costs immediately. We recommend making the switch sooner rather than later — especially if you're already relying on call forwarding to keep your business reachable.
Frequently Asked Questions
What is the code to divert a landline to a mobile in the UK?
The standard code is *21*[mobile number]#. Pick up your landline, dial this sequence (e.g., *21*07700900123#), and all incoming calls will be forwarded to your mobile. This works on BT, Sky, and TalkTalk. On Virgin Media, add an extra 0 before the mobile number: *21*0[mobile number]#.
How do I cancel call diversion on my landline?
To cancel an all-calls divert, pick up your landline and dial #21#. To cancel an unanswered-calls divert, dial #61#. You'll hear a confirmation tone when the diversion is deactivated. This works across BT, Sky, Virgin Media, and TalkTalk.
Is it free to divert landline calls to a mobile?
No. When you divert calls from a UK landline to a mobile, your provider charges you for the landline-to-mobile call. Rates typically range from 3.5p to 10.5p per minute depending on your provider and plan. These charges can add up significantly for businesses. VoIP systems usually include call forwarding at no extra cost.
Can I divert my landline to my mobile only when I don't answer?
Yes. Use the code *61*[mobile number]# instead of *21*. This will ring your landline first and only forward to your mobile if the call isn't answered within approximately 15–20 seconds. Cancel with #61#.
What is the best alternative to landline call diversion for a UK business?
The best alternative is a VoIP or hosted phone system. Unlike traditional call diversion, VoIP sends calls directly to a mobile app, desk phone, or laptop over the internet — with no per-minute forwarding charges. You keep your existing landline number, get features like auto-attendant and call recording, and typically pay from £6–£12 per user per month. This is especially relevant ahead of the UK's PSTN switch-off in 2027.
Does the *21* divert code work on Virgin Media?
Yes, but with a slight difference. On Virgin Media, you need to add an extra 0 before the mobile number. So the code becomes *21*0[mobile number]# — for example, *21*007700900123#. Forgetting the extra zero is a common reason the divert fails on Virgin lines.
