Call Forwarding: A Complete Guide

```html

⚡ Quick AnswerCall forwarding redirects your incoming calls to another number — such as a landline, mobile, or VoIP system — so you never miss important calls. You can set it up through your phone's settings, star codes (like *21*), or your network's app. This guide covers how to forward calls on every UK network, including all forwarding types: unconditional, no-answer, busy, and not-reachable call divert options.

Business call forwarding and diverting setup on UK mobile networks

Call Forwarding: A Complete Guide for UK Mobiles & Businesses

Whether you call it call forwarding, call divert, or simply call redirect, the concept is the same: routing your incoming calls to a different number so nothing gets missed. This comprehensive guide covers everything you need to know about how to forward calls — from quick star codes and step-by-step setup instructions to network-specific details and advanced business solutions. If you are a UK mobile user wondering how to divert calls, or a business looking to keep every customer call answered, you are in the right place.

How to Forward Calls on Any UK Network

If you need a quick reference for how to forward calls regardless of which UK network you are on, the table below has you covered. These universal GSM star codes work on EE, O2, Vodafone, Three, and all UK MVNOs. Simply open your phone's dialler, type the code (replacing [number] with the full destination number), and press Call.

Forwarding Type	Activate	Deactivate	Check Status
All calls (unconditional)	`21[number]#`	`#21#`	`*#21#`
When unanswered	`61[number]#`	`#61#`	`*#61#`
When busy	`67[number]#`	`#67#`	`*#67#`
When unreachable	`62[number]#`	`#62#`	`*#62#`
Cancel ALL forwarding	`##002#`	—	—

💡 Example: To divert all calls to 07700 900123, open your dialler and type *21*07700900123# then press Call. To cancel it, dial #21#. These codes work universally — so whether you are learning how to divert calls on EE or any other provider, the process is identical.

Keep reading for detailed, network-specific instructions, phone settings guides, and advanced business call forwarding solutions — or bookmark this table for future reference.

How Call Forwarding Works

Call forwarding (also called call divert) redirects incoming calls from your mobile to another number — a landline, another mobile, or a VoIP system. When someone dials your number, the network intercepts the call before or after your phone rings (depending on the type of forward you have set) and routes it to the destination number you have specified.

This ensures you never miss important calls, even when you are away from your phone, busy on another line, or in an area with no signal. Understanding how to forward calls is essential for both personal and business use. Call forwarding is a standard feature supported by every UK mobile network and requires no additional apps or hardware to use at a basic level.

💡 Good to Know: Call forwarding is handled at the network level, not by your handset. This means it works even if your phone is switched off or has a flat battery (for unreachable forwarding). It also means standard call charges may apply to the forwarded leg of the call, depending on your tariff.

Types of Call Forwarding

There are four standard types of call forwarding available on UK mobile networks. Each serves a different purpose when you need to know how to divert calls, and you can activate several simultaneously to cover every scenario:

Unconditional forwarding (all calls) — Every incoming call is forwarded immediately. Your phone does not ring at all. This is useful when you want all calls redirected to a colleague or office line.
Forward when busy — Calls are forwarded only when you are already on another call. This call divert option prevents callers from hearing an engaged tone.
Forward when unanswered — Calls are forwarded after a set number of rings (typically 15–30 seconds). Your phone rings first, giving you a chance to answer before the call is redirected.
Forward when unreachable — Calls are forwarded when your phone is switched off, in aeroplane mode, or out of signal range. This is critical for ensuring availability even during connectivity issues.

✅ Business Tip: For the best coverage, set up all three conditional forwards (busy, unanswered, and unreachable) to the same number — such as your office landline or a VoIP auto attendant. This way, callers are always routed somewhere helpful regardless of the reason you cannot answer. Get a free quote for business call forwarding solutions →

How to Forward Calls: Step-by-Step

There are three main methods to set up call forwarding on your mobile. Whether you want to know how to forward calls using a quick dial code or prefer navigating through settings menus, choose whichever method suits you best — they all achieve the same result at the network level.

Method 1: Using Star Codes (Fastest)

Star codes (also called USSD codes or call divert codes) are the quickest way to activate call forwarding. They work on every handset and every UK network — making them the go-to method when you need to know how to divert calls fast.

📞 Steps to Forward All Calls Using Star Codes

Open the Phone (dialler) app on your mobile.
Type the appropriate code. For example, to forward all calls to 07700 900123:
*21*07700900123#
Press the Call button (green phone icon).
Wait for a confirmation message on screen — you will see something like "Call forwarding — enabled" or hear a confirmation tone.
That is it. All incoming calls will now forward to 07700 900123.

🚫 Steps to Cancel Call Forwarding

Open the Phone (dialler) app.
Type:
##002#
Press the Call button.
Wait for the confirmation message — all call forwarding rules will be cancelled.

Method 2: Through Your Phone's Settings

If you prefer a menu-driven approach, you can set up call forwarding through your phone's built-in settings. This method gives you a visual interface for managing your call divert preferences. The exact steps differ between iPhone and Android — see our dedicated guides below:

📱 How to Set Up Call Forwarding on iPhone →
📱 How to Set Up Call Forwarding on Android →

Method 3: Through Your Network's App or Website

Most UK networks let you manage call forwarding through their customer app or online account portal. This is useful if you want to manage call divert settings remotely or on behalf of multiple business handsets. Log in to My EE, My Three, My O2, or My Vodafone and look for the call divert or call management section.

Call Forwarding Codes (Universal GSM Codes)

The following call forwarding star codes are standard across all UK mobile networks. These are the same codes shown in the quick-reference table above, presented here with additional detail. Replace [number] with the full phone number you want calls forwarded to (e.g. 07700900123 or 02071234567).

Action	Code to Activate	Code to Cancel	Code to Check Status
Forward all calls	`*21[number]#`	`##21#`	`*#21#`
Forward when busy	`*67[number]#`	`##67#`	`*#67#`
Forward when unanswered	`*61[number]#`	`##61#`	`*#61#`
Forward when unreachable	`*62[number]#`	`##62#`	`*#62#`
Cancel ALL forwarding	`##002#`	—	—

💡 Tip: You can use either *21* or **21* to activate call forwarding. The single-star version activates a new forward, whilst the double-star version registers and activates (useful if you have previously deactivated without deregistering). Both achieve the same result in most situations.

Call Forwarding Codes by Network

While the universal GSM codes above work on every UK network, some providers also offer their own shortcodes or have specific nuances worth knowing. Below you will find dedicated call forwarding instructions for each of the four major UK networks. If you are wondering how to divert calls on your specific provider, jump to the relevant section.

Call Forwarding on EE

EE supports all standard GSM call forwarding codes. Here is how to forward calls on EE:

Action	Code	Notes
Divert all calls	`21[number]#`	Your phone will not ring
Divert when unanswered	`61[number]#`	Diverts after ~15 seconds
Divert when busy	`67[number]#`	Activates when line is engaged
Divert when unreachable	`62[number]#`	Phone off or no signal
Cancel all diverts	`##002#`	Removes all call forwarding
Check divert status	`*#21#`	Shows current forwarding status

EE-specific notes: EE also allows you to manage call divert settings through the My EE app and online at ee.co.uk. If you are on an EE business plan, your administrator may be able to configure call forwarding centrally. Note that forwarded calls on EE may be charged at your standard call rate to the destination number — check your plan terms.

Call Forwarding on O2

O2 uses the same universal GSM codes and also provides a handy voicemail-specific shortcode. Here is how to divert calls on O2:

Action	Code	Notes
Divert all calls	`21[number]#`	Immediate forward — phone won't ring
Divert when unanswered	`61[number]#`	Rings for ~15 secs then diverts
Divert when busy	`67[number]#`	When already on a call
Divert when unreachable	`62[number]#`	Phone off / no signal
Cancel all diverts	`##002#`	Clears all call forwarding rules
Divert to O2 voicemail	`21901#`	O2-specific voicemail shortcode

O2-specific notes: O2 customers can also manage call forwarding settings via the My O2 app or by calling 202 from their O2 handset. O2 does not typically charge extra for forwarding calls to your O2 voicemail, but forwarding to another number may incur standard call charges. O2 Business customers can configure call divert through their O2 Business portal.

Call Forwarding on Vodafone

Vodafone supports all universal codes and offers some additional shortcodes for quick call divert setup. Here is how to forward calls on Vodafone:

Action	Code	Notes
Divert all calls	`21[number]#`	All calls go straight to destination
Divert when unanswered	`61[number]#`	Default ring time before divert: ~15 secs
Divert when busy	`67[number]#`	Engaged-line forwarding
Divert when unreachable	`62[number]#`	Phone off or out of coverage
Cancel all diverts	`##002#`	Removes all active call forwarding
Divert to Vodafone voicemail	`21121#`	Vodafone voicemail shortcode

Vodafone-specific notes: You can manage call forwarding through the My Vodafone app under Settings > Call divert. Vodafone also allows you to set a custom ring time for unanswered call divert using the extended code **61*[number]**[seconds]# — for example, **61*07700900123**20# sets a 20-second ring before forwarding. Vodafone Business customers can manage diverts through Vodafone Business Hub.

Call Forwarding on Three

Three (3) supports all standard GSM call forwarding codes. Here is how to divert calls on Three:

Action	Code	Notes
Divert all calls	`21[number]#`	Immediate — your phone won't ring
Divert when unanswered	`61[number]#`	Diverts after ~15 secs of ringing
Divert when busy	`67[number]#`	When your line is engaged
Divert when unreachable	`62[number]#`	Phone off or no coverage
Cancel all diverts	`##002#`	Clears all call forwarding settings
Divert to Three voicemail	`21+447782333123#`	Three's voicemail number

Three-specific notes: Three customers can manage call forwarding via the My3 app or online at three.co.uk. It is worth noting that Three may charge for forwarded calls that connect — typically at your standard per-minute rate. Three Business customers with multiple lines can configure call divert settings through the Three Business portal. If you are on a Three Pay As You Go plan, ensure you have sufficient credit before activating call forwarding, as the forwarded leg may use your balance.

📞 Need a smarter solution? If you are using mobile call forwarding as a workaround for your business, there may be a better way. A proper VoIP or hosted telephony system from Connection Technologies gives you intelligent call routing, auto attendants, hunt groups, and much more — without relying on network-level diverts. Get a free business telecoms quote →

How to Set Up Call Forwarding on iPhone

If you prefer using your phone's settings menu rather than star codes, here is how to forward calls on an iPhone:

📱 iPhone Call Forwarding Steps

Open Settings on your iPhone.
Scroll down and tap Phone.
Tap Call Forwarding.
Toggle Call Forwarding to on (green).
Tap Forward To and enter the destination phone number.
Tap Back — call forwarding is now active.

⚠️ Important: The iPhone settings menu only activates unconditional (all calls) forwarding. To set up conditional call divert options (busy, unanswered, unreachable), you will need to use the star codes listed above. Also note that the Call Forwarding option may not appear in Settings if your carrier does not support it through this menu — in that case, use star codes instead.

How to Set Up Call Forwarding on Android

Android phones offer more granular call forwarding controls through settings, letting you configure each forwarding type individually. Here is how to divert calls on Android:

📱 Android Call Forwarding Steps

Open the Phone app.
Tap the three-dot menu (⋮) in the top-right corner.
Tap Settings (or Call settings).
Tap Supplementary services or Call forwarding (wording varies by manufacturer).
Select the forwarding type: Always forward, When busy, When unanswered, or When unreachable.
Enter the destination number and tap Enable or Turn on.

Samsung Galaxy users: On Samsung devices, the path is typically Phone app > ⋮ > Settings > Supplementary services > Call forwarding > Voice call. From there, you can configure each call forwarding type individually — giving you full control over how to divert calls in every scenario.

Google Pixel users: On Pixel devices, navigate to Phone app > ⋮ > Settings > Calling accounts > [Your SIM] > Call forwarding.

Business Call Forwarding Solutions

While basic mobile call forwarding is useful for individuals, businesses typically need more powerful and flexible call routing. Simple star-code diverts lack features like time-based routing, multiple-destination forwarding, call queuing, and analytics — all of which are critical for professional customer service.

Limitations of Basic Mobile Call Forwarding for Business

Single destination only — You can only forward to one number at a time. There is no option to ring multiple phones simultaneously or create a hunt group.
No time-based rules — You cannot automatically change call divert behaviour based on time of day, day of week, or bank holidays.
No call queuing — If your forwarded-to line is busy, the call is lost or goes to voicemail. There is no hold queue.
No reporting or analytics — You have no visibility on how many calls were forwarded, answered, or missed.
Potential charges — Forwarded calls may incur per-minute charges on your mobile tariff, adding up quickly for businesses with high call volumes.
Manual management — Activating and deactivating call forwarding across multiple handsets is time-consuming and error-prone.

The Better Alternative: Hosted Telephony & VoIP

A hosted telephony or VoIP system from Connection Technologies gives you everything basic call forwarding offers — and far more:

Intelligent call routing — Route calls based on time of day, caller location, department, or agent availability.
Auto attendant (IVR) — Greet callers professionally and let them choose where to be connected.
Hunt groups & ring groups — Ring multiple phones simultaneously or in sequence until someone answers.
Call queuing with hold music — Keep callers waiting in a professional queue instead of sending them to voicemail.
Voicemail to email — Receive voicemail recordings as email attachments so nothing gets missed.
Detailed call analytics — Track call volumes, answer rates, peak times, and more via a web dashboard.
Remote management — Configure all call routing from a web portal — no need for star codes or per-handset setup.
Work from anywhere — Use softphone apps on mobiles, laptops, or desk phones. Calls follow you wherever you are.

🚀 Upgrade from Basic Call Forwarding

Get a professional business phone system with intelligent call routing, auto attendants, and analytics — from just a few pounds per user per month.

Get Your Free Quote →

Call Forwarding Troubleshooting

Having issues with your call forwarding setup? Here are solutions to the most common problems people encounter when learning how to forward calls:

Call Forwarding Won't Activate

Check your signal — Star codes require a network connection to register. Ensure you have at least one bar of signal or connect to Wi-Fi Calling.
Check the destination number — Make sure you are entering the full number including the area code (e.g. 07700900123, not 7700900123). Do not include spaces or dashes.
Clear existing forwards first — Dial ##002# to cancel all existing call forwarding rules, then try activating again.
Contact your network — Some Pay As You Go plans or specific tariffs may have call divert restricted. Contact your network to check.

Calls Are Not Being Forwarded

Check forwarding status — Dial *#21# (for unconditional) or the relevant status code to confirm call forwarding is active.
Check the forwarding type — If you set up "forward when unanswered" but your phone is off, calls will not be forwarded. You need "forward when unreachable" for that scenario. Set up all conditional types for complete coverage.
Destination number issues — Ensure the destination number is valid and able to receive calls. Try calling it directly to test.

Getting Charged for Forwarded Calls

This is expected behaviour on most UK mobile networks. When you activate call forwarding, the forwarded leg of the call is typically charged to you at your standard call rate.
If charges are a concern, consider forwarding to a VoIP number or using a hosted telephony solution where call routing is handled in the cloud without per-minute mobile charges.

Forwarding Loop / Calls Not Connecting

If you have forwarding set up on both the source and destination numbers (each forwarding to the other), this creates a loop and calls will fail. Ensure the destination number does not have call divert back to your original number.

Frequently Asked Questions About Call Forwarding

Is call forwarding free on UK mobile networks?

Setting up call forwarding is free, but the forwarded leg of the call may be charged at your standard per-minute rate. This means you could be billed for calls that are diverted to another number. Forwarding to your network's voicemail is usually free. Always check your specific tariff's terms regarding call divert charges.

Does call forwarding work when my phone is off?

Yes — but only if you have activated forward when unreachable (code *62*[number]#). This type of call forwarding is handled entirely at the network level, so it works when your phone is switched off, has a flat battery, or is in aeroplane mode.

Can I forward calls to an international number?

Yes, you can set up call forwarding to an international number by using the full international format (e.g. *21*+33612345678# for a French number). However, you will be charged international call rates for each forwarded call, which can become very expensive. For businesses with international teams, a VoIP solution is far more cost-effective.

What is the difference between call forwarding and call divert?

There is no difference — call forwarding and call divert are two names for the same feature. UK networks use both terms interchangeably. Some networks label the feature "call divert" in their settings and apps, whilst others use "call forwarding." The star codes and functionality are identical regardless of terminology.

How do I know if call forwarding is active on my phone?

Dial *#21# and press Call to check whether unconditional call forwarding is active. You can also check other types: *#61# for unanswered, *#67# for busy, and *#62# for unreachable. On most phones, you will also see a small phone icon with an arrow in your status bar when call divert is active.

Can I forward calls to multiple numbers at once?

Not with standard mobile call forwarding — you can only set one destination number per forwarding type. If you need calls to ring multiple phones simultaneously (a "ring group" or "hunt group"), you will need a VoIP or hosted telephony system. Connection Technologies can set this up for your business →

How do I cancel all call forwarding at once?

Dial ##002# and press Call. This universal code cancels all call forwarding rules on your number — unconditional, busy, unanswered, and unreachable — in one go. It works on all UK networks.

Will the caller know their call has been forwarded?

Generally, no. When call forwarding is active, the caller's experience is seamless — they hear ringing and the call is answered at the destination number. The caller will not receive a notification that the call has been diverted. However, they may notice a different person or voicemail greeting at the destination.

Can I set up call forwarding while I'm abroad?

Yes, you can activate call forwarding using star codes or phone settings whilst roaming abroad. However, be aware that forwarded calls may incur international roaming charges for both the incoming call and the forwarded leg. It is often more cost-effective to set up call divert before travelling, or to use a VoIP-based solution that routes calls over the internet.

💼 Need More Than Basic Call Forwarding?

Connection Technologies specialises in business telecoms solutions for UK companies. From hosted VoIP systems with intelligent call routing to SIP trunking and business mobiles — we can help you build a professional phone system that goes far beyond simple call forwarding.

Get a Free Quote → Speak to an Expert →

```