How to Divert Calls on the iPhone with GSM Codes

by Jo Meenen | Click to Follow Him on Twitter

gsmcodekeypadHave you ever tried to forward incoming calls on your iPhone to another phone? Some weeks ago, when I was trying out the BabyFon application, I had to do divert all incoming calls. If you search through the iPhone’s phone application to find a button which lets you divert calls, you will have no luck. Instead, you have to go to the settings application: Settings > Phone > Call Forwarding. In the menu you can enter a phone number where you want to have your calls forwarded to. In the same menu you can switch call forwarding on or off. There is also another way to forward calls. This is the solution I prefer as it comes in more handy when you need to use call forwarding on a day to day basis: you can use GSM codes and make convenient short cuts in your contacts database.

Do you wonder what GSM codes are? GSM is the abbreviation for Global System for Mobile Communications. This standard defines various codes with which you can control phones which implement this standard. For example, you can configure call forwarding and other similar options too. In this article we will look at call forwarding only. You can control lots of other features with GSM codes, which I will discuss in a later post.

These are the GSM codes of interest, if you need to divert calls on your phone:

  1. **21*a phone number#  – to register a phone number and activate the diversion of all calls to this number.
  2. *21# — to activate divert all calls function (supposed you already have registered a phone number in the past).
  3. #21# — to deactivate divert all calls.

You can enter these codes through the Phone’s keypad. Just open the phone application and tap on the Keypad tab. Enter **21*a phone number# to register a phone number to which you want to forward incoming calls. When you register a phone number, that will also activate call diversion. With the code #21# you can deactivate call diversion.

If you are like me you have every chance of forgetting to deactivate the forwarding function. Therefore, it might be a good idea to set an alarm in the clock application to remind you of turning off call diversion.

The next time you need to divert incoming calls, it is enough to enter the code *21#, as the number is already registered. If you need to divert to a different number you certainly can register a new number.

As I am not good in remembering GSM codes I have installed shortcuts in the address book. This is how you can do it:

  • Open the contact to whom you want to divert the call to.
  • Tap on the Edit button and select Add new Phone.
  • Enter the GSM code together with the number you want to forward calls to (e.g. **21*08150815#).
  • Press on the label beneath the phone field to add a custom field (Press Edit on the Label view, then select Add Custom Label).
  • Do the same steps once more to add a phone number which will deactivate the divert all calls function.

This is how you can use GSM codes to forward calls to another phone. Look through the list I have linked to for further useful GSM codes. For example, there are GSM codes with which you can hide your caller id when making phone calls. Check the Quick Tip category in the coming days. I will write another short post about the caller id soon.


{ 27 comments… read them below or add one }

Silus Grok August 13, 2009 at 10:52 am

Dayum. This — this is pure gold. Thanks!

Joe August 13, 2009 at 1:20 pm

Thanks for your kind words.

iphone application development September 23, 2009 at 10:33 pm

Look through the list I have linked to for further useful GSM codes.Interworld Commnet provides iphone and mobile application development, web & intranet application development, seo and internet have learn more visit @

walid ahmed June 29, 2010 at 6:54 am

this is really great, really smart solution,
can you please put the code for calls forward if not replied or busy?
Again thanks

Nat June 29, 2010 at 4:22 am

Is it possible to only divert only ONE specific number (using iphone ofcourse). One of my friends keep playing a prank on me and i have alrd told him off. But it would be better if i can block or divert that specific number.

Jessica July 29, 2010 at 4:29 am

Do u know how to divert calls only when there’s no answer?

lorna August 16, 2010 at 10:20 am

I’m the same as jessica, I dont know how to divert calls only when there is no answer. Can anyone tell me how to do this?

Ali October 30, 2010 at 11:55 pm

I really need to know if the iphon has the capability to divert or forward calls that are not answered , or does it have a delay diverting system like the Nokia.

With the Nokia you can set the divert to 20 or 30 seconds and if there is no answer it will automatically divert the incoming call to your choosen number.

J.S.B. November 5, 2010 at 11:43 am

I contacted Vodafone for information on turning off the call divert function. By email they contacted me and said entering ##002# would turn off all diverts. This has worked for me on the iPhone 3. Thought might be of interest to someone.

ET December 5, 2010 at 9:55 pm

#002# Works!!

unlocked gsm mobile December 26, 2010 at 6:56 am

Thanks for the wonderful tips it was very useful! Until next time!

Graham March 12, 2011 at 10:55 am

I am on Orange, last month I used my Iphone settings to forward my calls to the magic number I have (free Number on all Plans), as I have a nokia phone (which I need to record my calls, needed for work!) however, I was charged for this service, so I am interested to see if the GSM input will work without occurring the extra costs!

jess March 31, 2011 at 2:39 pm

thank you heaps! came in handy!

jess March 31, 2011 at 2:39 pm

thanks heaps!

apoorva May 22, 2011 at 6:46 am

life saving tips.. live long and prosper Joe!

Pablo Molinengo August 18, 2011 at 11:45 pm

como hago para desviar llamadas manualemnte con un iphone? es decir filtrarlas , algunas quiero atender y las que no desviar a una de mis asistentes.

con el desvio de llamadas que active de iphone pasan todas directas al tel que puse , sin dar opcion de atender.

khan September 19, 2011 at 12:26 pm

Is it possible to only divert only ONE specific number (using iphone ofcourse). One of my friends keep playing a prank on me and i have alrd told him off. But it would be better if i can block or divert that specific number.rite now i m using nokia x302

Sir Ebi Heart October 8, 2011 at 8:50 pm

How to send bulk sms on pc, also how to place an advant online

Immiejay November 9, 2011 at 10:52 am

check this app that sets up UK voicemail divert

Udhaya November 18, 2011 at 6:49 am

What about CDMA network?

Mike December 31, 2011 at 2:47 pm

i did everthing you said to divert calls on my iphone,but i just get “error preforming request,no network service” also “setting registration failed voice call forwarding on all call” etc,etc. I am on orange with wi-fi switched on and showing good signal strength,i wish i could sort this out because it would be a great option for me,any ideas ? Yours hopefully Mike. ps it’s an iphone 4.

May January 16, 2012 at 10:50 am

this is really helpful. I arrived at work today having forgotten my iphone at home. I asked my son to enter the codes above, and hey presto, all calls are diverted to my work number…. thank you

Archie January 18, 2012 at 4:26 pm

Can anyone actually tell me if it is possible on an iphone to divert a single number ONLY (without diverting all calls) from my contact list?? Ive seen this question asked a few times but not a single reply yet

vera January 30, 2012 at 11:08 am

can some telll me if i can record my calls with iphone 4s?

Jonty May 21, 2012 at 6:17 pm

These should work on all GSM networks as they are standards-based from my experience. i am guessing that users in the US do not have much experience with GSM so the information is not easily available.

Here are the codes that you have to dial in to the phone keypad to do each of the respective actions:

short codes to dial for setting call diverts:

**67*[divert number]*# — when busy
**61*[divert number]*# — when not reachable
**62*[divert number]*# — when switched off
**21*[divert number]*# — divert all calls

##002# — cancel all diverts

replace [divert number] with number to divert to.

i hope this is useful to anyone out there.

Jeny Michaels July 4, 2012 at 7:59 am

Try these:
Call Forwarding Unconditional
- When you use Call Forwarding, incoming calls to your Landline are sent to another fixed-line or mobile number. Alternatively, you can forward calls to your voicemail or to a fax or pager number
Three Call Forwarding services are available for Landlines
Forward all calls:
- To activate: *21*+(forwarding telephone number)#
- To deactivate: #21#
On no reply:
- *61*+(forwarding telephone number)#
- To deactivate: #61#
On Busy :
- *67*+(forwarding telephone number)#
- To deactivate: #67#

Call Barring
- Use your secret 4-digit code to control who makes national and international calls using your home Landline.
- National and International call barring is easy to set up.
- To activate: *33* (4 pin code)#
- To deactivate: #33* (4 pin code)#

Charlotte White June 8, 2013 at 11:52 am

Like Nat, I would also like to know if it’s possible to do this just for one specific number. i.e. one person who calls me who can be diverted straight to voicemail, or to a dead phone!

Either that, or I have to change my number.

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