Updated: April 2026 · Reviewed by: Connection Technologies Telecoms Team
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How to Divert Calls from Landline to Mobile UK: Complete 2026 Guide
✅ Quick Answer: The Universal Divert Code
To divert all calls from your UK landline to a mobile, pick up your handset and dial:
*21*your mobile number#
For example: *21*07700900000#. You’ll hear a confirmation tone. To cancel, dial #21#.
This code works on BT, Sky, TalkTalk, Plusnet, and most other UK landline providers using the Openreach network. You will be charged standard landline-to-mobile rates (typically 10p–20p per minute) for every diverted call. For businesses needing permanent call routing, VoIP is a far cheaper long-term solution ↓
Whether you’re stepping out of the office, working remotely, or simply need to ensure you never miss an important business call, knowing how to divert calls from your landline to your mobile in the UK is essential. Call diversion — sometimes called call forwarding — routes incoming landline calls directly to your mobile phone, keeping you connected wherever you are.
In this comprehensive guide, we’ll walk you through the exact setup process for every major UK provider, explain the costs involved, and show you why modern VoIP solutions like HyperCloud offer a far superior — and often more cost-effective — alternative for businesses that rely on permanent call forwarding.
What Is Call Diversion and How Does It Work?
Call diversion is a telephony feature that automatically redirects incoming calls from one number to another. When you divert calls from your landline to your mobile, the caller dials your landline number as normal, but the call rings on your mobile instead. The caller typically doesn’t know the call has been redirected — they simply hear the phone ringing.
There are several types of call diversion available on most UK networks:
- Unconditional diversion (
*21*): All calls are forwarded immediately, regardless of whether you’re on the phone or not. - Divert on no answer (
*61*): Calls forward after a set number of rings if you don’t pick up. - Divert on busy (
*67*): Calls are only forwarded when your landline is engaged. - Divert on unavailable: Calls forward when your line is out of service or disconnected.
For a deeper look at the differences between these options and more advanced configurations, read our full guide on call forwarding for business.
How Do You Set Up Call Diversion on BT, Sky, TalkTalk, and Plusnet?
The process varies slightly depending on your landline provider, but the star codes are universal across most UK Openreach-based networks. Below, you’ll find step-by-step instructions for BT, Sky, TalkTalk, and Plusnet — the UK’s most popular residential and business landline providers.
How to Divert Calls on a BT Landline
BT uses standard star codes dialled directly from your landline handset. Here’s how to set up each type of diversion:
- Divert all calls: Pick up your handset and dial
*21*[mobile number]#— for example,*21*07700900000#. You’ll hear a confirmation tone. - Divert on no answer: Dial
*61*[mobile number]# - Divert when busy: Dial
*67*[mobile number]#
To cancel call diversion on BT:
- Cancel all-call divert: Dial
#21# - Cancel no-answer divert: Dial
#61# - Cancel busy divert: Dial
#67#
How to Divert Calls on a Sky Landline
Sky Talk uses the same star code system as BT for call diversion:
- Divert all calls: Dial
*21*[mobile number]# - Divert on no answer: Dial
*61*[mobile number]# - Divert when busy: Dial
*67*[mobile number]#
Cancellation codes are identical to BT. You can also manage some diversion settings through the Sky customer portal or by contacting Sky’s customer service team.
How to Divert Calls on a TalkTalk Landline
TalkTalk also supports the standard divert codes:
- Divert all calls: Dial
*21*[mobile number]# - Divert on no answer: Dial
*61*[mobile number]# - Divert when busy: Dial
*67*[mobile number]#
To deactivate, use the corresponding #21#, #61#, or #67# codes. TalkTalk customers should note that call divert may need to be activated on your account first — check your My Account dashboard or ring TalkTalk support.
How to Divert Calls on a Plusnet Landline
Plusnet, which operates on the BT Openreach network, uses the same codes:
- Divert all calls: Dial
*21*[mobile number]# - Divert on no answer: Dial
*61*[mobile number]# - Divert when busy: Dial
*67*[mobile number]#
Plusnet customers can also manage call features through the Plusnet Member Centre. Cancellation follows the same # codes outlined above.
Quick Reference: All UK Landline Divert Codes
| Action | Activate Code | Cancel Code |
|---|---|---|
| Divert all calls | *21*[mobile number]# | #21# |
| Divert on no answer | *61*[mobile number]# | #61# |
| Divert when busy | *67*[mobile number]# | #67# |
These codes work on BT, Sky, TalkTalk, Plusnet, and most other Openreach-based UK landline providers.
How Much Does Landline Call Diversion Cost in the UK in 2026?
This is where many businesses get caught out. While setting up call diversion is usually free, you will be charged for every diverted call. The costs can add up quickly, particularly if you receive a high volume of calls.
| Provider | Diversion Cost (2026) | Notes |
|---|---|---|
| BT | ~13p–20p per minute (standard mobile rate) | Not included in calling plans; charged per minute |
| Sky | ~15p–20p per minute (standard mobile rate) | Diverted calls use your call allowance or are charged at standard rates |
| TalkTalk | ~12p–18p per minute (standard mobile rate) | Calls to mobiles are typically not included in free call packages |
| Plusnet | ~13p–20p per minute (standard mobile rate) | Check your plan for mobile minute allowances |
| HyperCloud VoIP (Connection Technologies) | £0 — included in plan | Calls route via app/softphone at no extra forwarding cost |
As a rough guide, landline-to-mobile call charges across these providers typically range from 10p to 20p per minute. For a business receiving 50 diverted calls per day, each averaging three minutes, that could equate to £15–£30 per day — or upwards of £400–£600 per month.
This ongoing expense is one of the primary reasons growing businesses explore VoIP-based alternatives.
Our recommendation: If your monthly diversion charges exceed £50, you’ll almost certainly save money switching to hosted VoIP. Get a free comparison quote →
Divert Codes vs VoIP: How Do They Compare?
The table below compares traditional landline call diversion with a hosted VoIP solution like Connection Technologies’ HyperCloud, so you can see exactly where each option wins — and where it falls short.
| Feature | Landline Divert Codes | HyperCloud VoIP |
|---|---|---|
| Setup method | Dial *21* from handset | Online portal, app, or managed by CT |
| Cost per diverted call | 10p–20p per minute ❌ | £0 — included ✅ |
| Estimated monthly cost (50 calls/day) | £400–£600/month ❌ | From £6–£15/user/month ✅ |
| Keep your business number | Yes ✅ | Yes — number ported ✅ |
| Answer on mobile app | Rings personal mobile only | Dedicated business app ✅ |
| Answer on laptop/desktop | No ❌ | Yes — softphone ✅ |
| Ring multiple team members | No — one number only ❌ | Yes — ring groups, hunt groups ✅ |
| Auto-attendant / IVR | No ❌ | Yes ✅ |
| Time-based routing | No ❌ | Yes — route by time of day, day of week ✅ |
| Voicemail to email | No ❌ | Yes ✅ |
| Call recording | No ❌ | Yes — included or add-on ✅ |
| Caller sees your business number | Caller sees landline number ✅ | Caller sees business number ✅ |
| Scalability | Limited — one line ❌ | Add/remove users in minutes ✅ |
| Best for | Temporary, emergency diversion | Permanent business call routing |
Our pick: For any business diverting calls regularly — even a few times per week — HyperCloud VoIP from Connection Technologies is the clear winner. It eliminates per-minute diversion charges entirely, gives you professional features traditional landlines can’t match, and typically costs less than what most businesses spend on call diversion alone.
Get Your Free HyperCloud Quote →
Is There a Better Alternative to Call Diversion for UK Businesses?
Yes. Traditional call diversion is a quick fix, but it was never designed for businesses that need permanent, flexible call routing. If you’re regularly diverting landline calls to mobiles — or to multiple team members — a hosted VoIP (Voice over IP) phone system is a far more powerful and cost-effective permanent solution.
💡 The Better Alternative: HyperCloud Hosted VoIP
Instead of paying 10p–20p per minute to divert every single call, HyperCloud replaces your landline entirely with a cloud phone system that works on your desk phone, mobile, laptop, and tablet — all using your existing business number.
- £0 call forwarding costs — calls route over the internet, included in your plan
- From £12/user/month — typically cheaper than what you’re already spending on diversions
- Your number, everywhere — we port your existing landline number across, so customers notice nothing
- Professional features — auto-attendant, ring groups, voicemail-to-email, call recording, time-based routing
- Set up in days, not weeks — Connection Technologies handles migration with zero downtime
Think of it this way: Divert codes are a plaster. HyperCloud is the cure. If you’re diverting calls more than occasionally, you’re overpaying for an inferior experience.
What Are the Key Advantages of VoIP Over Traditional Call Diversion?
- No per-minute diversion charges: VoIP calls route over the internet, meaning forwarding to mobiles, softphones, or other devices is typically included in your plan at no extra cost.
- Use your business number anywhere: Answer calls on your desk phone, mobile app, laptop, or tablet — all from your existing business number.
- Advanced call management: Set up ring groups, hunt groups, auto-attendants, time-based routing, and voicemail-to-email — features traditional landlines simply cannot match.
- Scalability: Add or remove users in minutes, without engineers or hardware changes.
- Professional image: Callers always see your business number, not a personal mobile — and you can manage every aspect from an online portal.
- Microsoft Teams integration: HyperCloud integrates with Teams for businesses already using Microsoft 365.
Connection Technologies’ HyperCloud hosted VoIP platform is built specifically for UK businesses that need reliable, feature-rich telephony without the limitations and costs of traditional landline diversions. With HyperCloud, your team can take business calls on any device, from any location — with crystal-clear call quality and enterprise-grade security.
Ready to Ditch Expensive Call Diversion?
If you’re paying to divert landline calls to mobiles every day, it’s time to consider a hosted VoIP solution that gives you total flexibility at a fraction of the cost. Connection Technologies can design a bespoke system tailored to your business — and we’ll port your existing number so your customers won’t notice a thing.
When Should You Use Traditional Call Diversion vs VoIP?
Traditional landline call diversion still has its place — it’s ideal as a temporary, short-term measure. For example:
- You’re moving offices and need calls routed for a few days.
- A staff member is out of the office unexpectedly and needs calls redirected immediately.
- You’re testing whether remote working is viable before committing to a new phone system.
- Your broadband is down and you need an emergency fallback for a few hours.
However, if call diversion is something you rely on daily or weekly, the costs and limitations of traditional forwarding make VoIP the clear winner.
| Scenario | Use Divert Codes? | Use VoIP? |
|---|---|---|
| Office move (1–3 days) | ✅ Yes | Optional |
| Emergency cover (staff illness) | ✅ Yes | Optional |
| Regular remote/hybrid working | ❌ Too expensive | ✅ Yes |
| Multi-site business | ❌ Not practical | ✅ Yes |
| Team of 5+ needing call routing | ❌ One destination only | ✅ Yes |
| Permanent “work from anywhere” | ❌ Costs £400+/month | ✅ From £12/user/month |
Best for small businesses diverting calls daily: Switch to HyperCloud VoIP. Connection Technologies regularly helps businesses make this transition smoothly, porting existing numbers and configuring systems with minimal disruption — often within 5 working days.
Speak to our team about transitioning from landline diversion to VoIP →
What Are the Pros and Cons of Landline Call Diversion?
Before you decide whether to use traditional divert codes or switch to a VoIP solution, here’s an honest breakdown of the advantages and disadvantages of landline call diversion.
✅ Pros of Landline Call Diversion
- Instant setup — dial a code and it’s active in seconds
- No equipment needed — works from any landline handset
- No contract or commitment — activate and cancel at will
- Works with any mobile number — UK or international
- Free to activate — no setup fees on any major UK provider
- Ideal for emergencies — perfect short-term fallback
❌ Cons of Landline Call Diversion
- Per-minute charges — 10p–20p/min for every diverted call adds up fast
- Can only divert to one number — no team routing or ring groups
- No call management features — no auto-attendant, voicemail-to-email, or call recording
- Shows personal mobile to caller if you call back (not your business number)
- No analytics or reporting — you can’t track call volumes or missed calls
- Expensive at scale — can cost £400–£600/month for busy businesses
- Not designed for permanent use — a temporary workaround, not a proper solution
Our verdict: Landline call diversion is useful in a pinch, but the costs and limitations make it unsuitable for any business relying on it regularly. For permanent call routing, hosted VoIP is the clear upgrade.
Frequently Asked Questions
Pick up your BT landline handset and dial *21* followed by your mobile number, then #. For example: *21*07700900000#. You’ll hear a confirmation tone indicating the diversion is active. To cancel, dial #21#. Note that you’ll be charged standard landline-to-mobile rates (typically 13p–20p per minute) for each diverted call. This code also works on Sky, TalkTalk, and Plusnet landlines.
Yes. While activating call diversion is generally free, each diverted call is charged at your provider’s standard landline-to-mobile rate — typically between 10p and 20p per minute in 2026. These charges are billed to the landline account holder, not the caller. Calls to mobiles are usually excluded from inclusive call packages. For businesses receiving high call volumes, this can cost £400–£600 per month — making hosted VoIP a far more cost-effective alternative.
Technically yes — the unconditional divert code (*21*[mobile number]#) remains active until you cancel it with #21#. However, permanent diversion via a traditional landline can be very expensive due to per-minute charges (potentially £400–£600/month for a busy business). For permanent call routing, a hosted VoIP solution like Connection Technologies’ HyperCloud is far more cost-effective and feature-rich, allowing you to receive calls on your mobile, laptop, or desk phone with no per-minute forwarding charges.
The universal code to divert all calls from a UK landline to another number is *21*[destination number]#. For example, to divert to mobile number 07700 900 000, dial *21*07700900000# from your landline handset. This works on BT, Sky, TalkTalk, Plusnet, and most other UK landline providers. To cancel, dial #21#.
It depends on the type of diversion and your provider. Unconditional diversion (*21*) is typically set at the exchange level, so it should continue working even if your handset is unplugged — as long as your line is still active with your provider. However, if your line is fully disconnected or cancelled, diversion will stop. For a reliable solution that works regardless of physical line status, consider a hosted VoIP system that routes calls over the internet.
For any small business that regularly diverts calls, yes — VoIP is significantly better. A hosted VoIP system like HyperCloud from Connection Technologies costs from £6 per user per month, includes call forwarding to any device at no extra charge, and adds professional features like auto-attendant, ring groups, voicemail-to-email, and call recording. Traditional call diversion charges 10p–20p per minute with no additional features. For occasional, temporary use, divert codes are fine — but for daily use, VoIP saves money and delivers a far better experience for both your team and your callers.
Stop Paying Per Minute. Start Routing Calls Properly.
Connection Technologies helps hundreds of UK businesses replace expensive call diversion with HyperCloud hosted VoIP — keeping your existing number, cutting costs, and giving your team the flexibility to work from anywhere.
No obligation · Free consultation · Number porting included · Typically live within 5 working days
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