How to send missed calls to another number on EE, O2, Vodafone and Three

Call diversion (or call forwarding) is the unglamorous little feature that decides whether a missed call becomes a lost customer. Set it up right and any call you cannot answer rings somewhere useful instead of becoming a lost customer: a colleague, a family member, or a service like ours that texts the caller back.

The catch: every UK network does it differently, the official instructions are scattered, and one iPhone setting quietly does the wrong thing. We learned all of this the hard way while setting up small businesses on Cuppa, so here is the guide we wish existed.

First: the one decision

There are two kinds of divert:

Divert all calls - every call goes straight to the other number. Almost never what you want.
Divert when unanswered, busy or unreachable - your phone rings first, and only the calls you miss go elsewhere. This is the one you want.

Keep that distinction in mind, because it matters on iPhone especially.

O2 (and giffgaff, Tesco Mobile, Sky Mobile)

O2 is the one UK network that properly documents its divert codes, and they work on its budget brands too. Dial these like a phone number:

Divert when unanswered: '**61*NUMBER*11#' then call
Divert when busy: '**67*NUMBER*11#'
Divert when unreachable (phone off / no signal): '**62*NUMBER*11#'
Check what is set: '*#61#' (and '*#67#', '*#62#')
Cancel all diverts: '##002#'

Replace NUMBER with the full number you want missed calls to go to. To control how long your phone rings first, add the seconds: '**61*NUMBER*11*30#' rings for up to 30 seconds before diverting.

EE (and 1pMobile, spusu, Lyca)

EE does not publish dial codes. Instead it steers you to your phone's own settings:

Android: Phone app > Settings > Calling accounts (or Supplementary services) > Call forwarding, then set "When unanswered", "When busy" and "When unreachable".
iPhone: see the warning below before touching anything.

Vodafone (and VOXI, Talkmobile)

Same approach as EE: use the handset's call forwarding settings rather than codes.

One hard exception: Vodafone Pay as you go can only divert to voicemail. If you are on Vodafone PAYG and want missed calls going anywhere else, you will need to move to a Pay monthly plan first.

Three (and Smarty, iD Mobile)

Three publishes no divert codes at all. Handset settings are the only route - and on iPhone, see below, because Three is where the iPhone problem bites hardest.

The iPhone gotcha (read this before you touch Settings)

On most networks, iPhone's Settings > Apps > Phone > Call Forwarding toggle is divert all calls. Flip it and your phone never rings again - every call goes straight to the other number. That is fine if it is what you meant, and a nasty surprise if it is not.

For "only when I do not answer", use your network's codes (O2) or, where the network only supports handset settings, test carefully: set it, then have someone call you and let it ring. If your iPhone still rings first, you are set. If it never rings, you have forwarded everything - undo it and use the network's route instead.

Two things worth knowing before you rely on it

Your tariff may charge for the diverted leg. A call forwarded onwards can count as an outgoing call from your plan. Check your network's current terms before assuming it is free.
A divert is only as good as what answers at the other end. If the second number just rings out too, the caller got silence twice. Whatever the calls divert to - a person, voicemail, or a text-back service like Cuppa - make sure something always responds.

And that is it. Ten minutes, one test call, and no missed call ever dies in a voicemail box again.

Curious what the missed calls are costing you? The missed-call calculator gives you an honest figure in thirty seconds.

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