How do I set up call forwarding?

There are two ways in. Short codes work on almost every mobile carrier: a star, a code, the destination number, and a hash. Dashboards are how VoIP and business lines do it, and they usually give you more options.

Pick the mode before you start, because the codes differ. Forward everything, forward when busy, forward when there is no answer, or forward on a schedule.

Write down what you set. Forwarding you have forgotten about is the single most confusing thing to debug six months later.

Get the destination number from GreetKeeper first. Enter it exactly, including the country code if your carrier expects one.

Set the ring count if you are using no-answer forwarding. The number is yours to choose: long enough for someone to reach the phone, short enough that the caller is not left waiting.

Now test it from a different phone. Let it ring through and listen to what happens, then read the transcript that arrives.

The four common mistakes: forwarding to the wrong number by a digit, leaving voicemail switched on so it grabs the call before forwarding does, setting a ring count longer than the carrier's own voicemail timer, and forgetting that a second line in the business is not forwarded at all.

Say you're a solo electrician on a mobile plan that uses the standard GSM codes, as AT&T, T-Mobile and the carriers on their networks do. You want calls to forward only when you don't pick up. So you dial **61*, then the ten-digit number GreetKeeper gave you, then **20#, and press call. The 20 is the delay in seconds, and on most of these carriers it can be anything from 5 to 30 in steps of five.

Twenty seconds is about three or four rings, since a US ring cycle lasts six seconds. Your screen shows a confirmation. You borrow your neighbor's phone, call yourself, let it ring, and hear the assistant pick up. A minute later the transcript of your test arrives.

To undo it, you dial ##61# and press call. Verizon uses different codes: *71 plus the number for no-answer forwarding, *72 plus the number for everything, and *73 to cancel. Carriers change these, so confirm any code list, this one included, before relying on it.

A traditional landline usually takes *72 and the destination number, and many phone companies only activate the forward once the destination answers that first call. If nobody picks up, you repeat the code within a couple of minutes to confirm it, and skipping that second step is why nothing forwards.

On an iPhone, the Call Forwarding switch in Settings only does the forward-everything mode. For no-answer or busy forwarding you need the codes or your carrier's app.

Office systems move the setting up a level. With a hosted VoIP system or a desk PBX that has an auto attendant, forwarding the handset on your desk does nothing for calls the system answers first. Change the rule in the admin dashboard instead.

Lines in a hunt group need care. When line one is busy, the phone company rolls the call to line two, then three. Put the no-answer forward on the last line in the chain, or calls will jump to the assistant while a free line sits silent.

GreetKeeper gives you the destination number and the code or dashboard path for your carrier, so you are not guessing at star codes from a forum post.

The first test call shows up as a transcript within a minute. That is your confirmation that the forward is live, and it is more reliable than the carrier's confirmation beep.

If voicemail is competing with the forward, the transcript will not appear and the call will go to voicemail. Turn voicemail off on that line and test again.