UK mobile network Checked September 2026
O2 call divert codes
To divert calls you don't answer on O2, dial **61*NUMBER*20#, putting the number you want in place of NUMBER. The 20 is how many seconds your phone rings first, and ##002# cancels every divert.
- 20-second ring example
- Cancel all with ##002#
- Voicemail is 901
**61*07700900123*20#Dial it from the phone you want to forward, then wait for the confirmation.
- Turn off
All O2 call divert codes
Replace NUMBER with the number you want calls to go to.
| Divert calls | Turn on | Turn off |
|---|---|---|
| No answer | **61*NUMBER*20#
Off: ##002# | ##002# |
| Busy | **67*NUMBER#
Off: ##002# | ##002# |
| Unreachable | **62*NUMBER#
Off: ##002# | ##002# |
| All calls | **21*NUMBER#
Off: ##002# | ##002# |
How to divert calls on O2
- 1
Check when calls will divert
This code sends calls you do not answer to the destination number.
- 2
Dial the code
From your O2 mobile, dial **61*NUMBER*20#, replacing NUMBER with the number calls should go to.
- 3
Check the result
Follow any prompts on your phone. If the request is rejected, check the instructions for your service before trying again.
- 4
Test it
Ring your number from another phone without answering it. Check that the destination receives the call. To turn it off later, dial ##002#.
How to turn off call divert on O2
Dial the code that matches the divert you set up. Calls go back to ringing your phone as normal.
- Every divert at once
-
##002#
What to know about call divert on O2
O2's guides show these codes with 901
O2 publishes these codes in its device guides for setting up voicemail, so they appear with 901, O2's voicemail number, as the destination: **21*901#, **61*901*20#, **62*901# and **67*901#. To divert somewhere else, swap 901 for the number you want.
Turning diverts off
O2's guides give one code for switching diverts off: ##002# cancels all of them at once, including the divert to voicemail. If you want voicemail back afterwards, set the divert again with 901, or call 1750 free if Voicemail 901 has been switched off.
Divert calls from your phone's settings
Your phone may also offer call forwarding in its settings, depending on your device and plan. The iPhone Call Forwarding switch sends every call on. Use a supported no-answer option if you want your phone to ring first.
iPhone
- Open Settings, then Apps, then Phone (on older iOS, Settings then Phone).
- Tap Call Forwarding and switch it on. If you use two SIMs, choose your business line first.
- Tap Forward To and enter the number calls should go to.
- Go back. A forwarding icon shows in the status bar while it is on.
Android
- Open the Phone app, tap the three-dot menu, then Settings.
- Tap Calls (or Supplementary services, depending on the phone), then Call forwarding.
- Choose When unanswered so your phone rings first and only missed calls move on.
- Enter the number, tap Turn on, and pick the right SIM if asked.
If the code doesn't work
"Connection problem or invalid MMI code"
The network did not accept the request. Check you have signal, turn off Wi-Fi calling and aeroplane mode, then dial the code again exactly as shown.
"Setting activation failed" or "unsuccessful"
The network refused the divert. Some plans block diverts to other numbers, and some networks want the number in international form. Check the notes on this page, or set it up in your phone settings instead.
Calls still go to voicemail
Voicemail is itself a divert, and only one can be active for each condition. Setting a new divert replaces the voicemail one. If calls still reach voicemail, cancel all diverts and set yours again.
O2 call divert questions
How do I divert calls on O2 to another number?
Dial **21* then the number and # to divert every call. To have your phone ring first, dial **61*, the number, *20# instead, so calls you do not answer within 20 seconds move on.
How do I turn off call divert on O2?
Dial ##002# and press call. It cancels every divert on your O2 number, including the one to voicemail. To get voicemail back, dial the divert code again with 901 as the number.
Why do O2 divert codes have 901 in them?
901 is O2's voicemail number, and O2's device guides show the divert codes with voicemail as the destination. Put the number you want in place of 901 to divert calls somewhere else.
How long does an O2 phone ring before it diverts?
The published example uses 20 seconds. O2 says the number of seconds must be divisible by 5, but its device guide does not state the full permitted range.
Is call divert free on O2?
O2's help pages do not list a price for diverted calls, so check with O2 how your plan bills them if you plan to divert a lot of calls.
Sources
Checked in September 2026 against the official pages below. Networks change codes and prices, so if something here stops working, their page is the final word.
