Conditional call forwarding, explained without the jargon

What conditional call forwarding means

Conditional call forwarding tells your carrier one thing: ring my phone as usual, and if I don't answer, send the call to this other number. The "condition" is you not picking up. That's all the word is doing.

Carriers split "not picking up" into three cases. You let it ring out (no answer). You're already on a call (busy). Or your phone is off, flat, or somewhere with no signal (unreachable). Some carriers set the lot with one code and some want a code for each. We'll get to which.

The other kind is plain call forwarding, which you'll also see called forward-all or unconditional. Every call goes to the other number and your own phone stays silent. It's useful, but it's a different tool, and people mix the two up all the time.

Which one do you want?

For most people, on most days, conditional. Your phone still behaves like your phone. Your sister rings, you answer, nothing has changed. Only the call that arrives while you're under a sink or in a meeting gets sent on.

Forward-all is for the day you really are gone. A long flight. A day off where you've promised not to look. A week when the number painted on the van needs answering by somebody else.

And where do the calls go? Anywhere with a phone number. A business partner, the office landline, an answering service, or an AI line that holds the conversation and writes it down. We make the last kind, so that's the example further down, but the codes are the same whatever is on the other end.

The codes, carrier by carrier

Dial these from the mobile you want to forward, the same way you'd dial a phone number. Where it says "the number", use the ten digits of the place you're sending calls to, area code first.

Smaller brands usually follow the network they run on, so a phone on Verizon's network tends to take Verizon's code. Codes can vary by plan, though. If one doesn't take, your carrier's own support page is the authority, not us.

• Verizon. Dial *71 followed by the number. One code does it. Wait for the confirmation tone or message, then hang up.
• AT&T. Dial *61*1 followed by the number, then #. That covers calls you don't answer. For busy it's *67*1, the number, then #. For unreachable it's *62*1, the number, then #. Dial each in turn and look for the confirmation on screen.
• T-Mobile. The same three codes as AT&T, dialed the same way.

If you'd rather use the phone's menu

Android phones have the same three conditions in the call settings, under call forwarding: one for when you're busy, one for when you don't answer, one for when you can't be reached. Set each to the number you want and you're done.

The iPhone is the catch. Its call forwarding switch forwards every call, not only the missed ones. So on an iPhone, use the carrier codes above (or your carrier's own app) when you want missed calls only. Plenty of people flip that switch, wonder why the phone has gone quiet, and find out at dinner.

How to test it in a minute

Don't take the confirmation tone's word for it. Test.

Have someone call your mobile, or call it yourself from another phone, and leave it ringing. Don't decline the call, just let it go. After the usual number of rings it should hop to the forwarding number. Then try again while you're on another call, and once more with the phone in flight mode, so busy and unreachable are covered too.

If you forwarded to a CosVoice line, the caller hears your assistant say you can't pick up right now and offer to help. About a minute after they hang up, a written summary arrives marked "Missed on mobile". In Settings, the Replace voicemail section shows the codes with your line's number already filled in, which saves you mistyping a string of stars and digits. The voicemail page has the same codes, and forwarding missed calls to an AI covers what the caller gets.

How to turn it off

Forwarding stays on until you cancel it. It doesn't expire, and it doesn't know you've changed your mind. So when you're done with it, cancel with a code from the same mobile.

• Verizon. Dial *73.
• AT&T and T-Mobile. Dial #61# to cancel the no-answer forward, #67# for busy, and #62# for unreachable.

Check it really is off

Same test, in reverse. Call your mobile from another phone, let it ring out, and listen for what answers. If it's your old voicemail greeting, forwarding is off. If it's still the other number, one of the three conditions is still set, and on AT&T or T-Mobile that usually means you canceled no-answer and forgot busy or unreachable.

It's a small thing. But a forward you've forgotten about is how calls end up somewhere nobody is looking.

Two things that catch people out

Cost. Some carriers count the forwarded part of a call against your mobile plan's minutes. Most people never notice, but check if your plan is a small one. Whatever answers at the other end may count the time too. On our lines a forwarded call uses plan minutes like any other call, and the pricing page has the details.

Ring time. How long your phone rings before the call moves on is set by the carrier. Some let you change it, some don't. If callers are hanging up before the forward kicks in, ask your carrier whether the ring time can be shortened. If you keep missing calls you were about to answer, ask for longer.

One last habit worth having: write down which codes you dialed and when. In six months you won't remember, and the person who inherits your phone number at work certainly won't.

Common questions

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