Written by: Emily Chen

List of USSD Codes & GSM Codes

Do you know the smartphone codes – USSD or GSM codes? We explain in this article what the cell phone codes are all about and how you can use them on your Android phone or iPhone.

You can access the hidden functions on your smartphone via the so-called USSD or GSM codes. Using a short string of numbers and characters, you can, for example, display your own phone number, set up call forwarding or check your prepaid balance. Some functions depend on the operating system (Android or iOS) or your mobile carrier.

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GSM codes & USSD codes

What are USSD codes or GSM codes?

Global System for Mobile Communication (GSM) and Unstructured Supplementary Service Data (USSD) are cell phone codes or smartphone codes that have been used since the early days of mobile telephones and cell phones.

With the individual GSM codes you can, for example, change services such as call forwarding, mailbox or SIM card settings. These codes are the same in all common mobile networks.

The USSD codes, on the other hand, refer to the individual communication and network providers and can therefore differ in detail.

However, both codes have one thing in common:

The cell phone codes are used to control functions in the cell phone or settings related to the network. In other words, they can be used to display your phone number or your prepaid credit or to change your network settings.

Depending on the network provider, different functions are available to you.


How to use the codes

Cell phone codes are entered via the phone’s call app or your phone number field:

Most cell phone codes use the hash “#” symbol and the asterisk “*” as special characters.

Between the two special characters you simply enter the desired combination of numbers. The codes are activated automatically after the input or you confirm the input with the handset symbol ✆.

All important USSD & GSM cell phone codes

As mentioned above, the smartphone codes are device- and network-dependent. It is therefore possible that not all of the codes presented here will work on your device.

To give you an overview, we have divided the cell phone codes into general GSM codes and device-specific codes for Samsung, Huawei and the iPhone.

Be careful.

If you don’t know exactly what one of the codes does, be careful. Use the presented cell phone codes at your own risk!

Please remember that many codes work only after confirmation (tapping the handset icon ✆).

List of GSM Codes

GSM CodesFunctionality
*#06#Check if phone is eSIM compatible (EID Number) / Call up the serial number or IMEI of the phone
*135#Query of the own phone number
**04*old PIN*new PIN*new PIN#Change PIN
**05*old PUK*new PIN*new PIN#Unlock phone with PUK
**042*old PIN2*new PIN2*new PIN2#Change PIN 2
**052*old PUK2*new PIN2*new PIN2#Unlock phone with PUK 2
*31#Own phone number is transmitted with call, is to be replaced accordingly by the dialing number
*30#Switch on caller ID display of incoming calls
#30#Switch off caller ID display of incoming calls
*43#Call waiting on
#43$Call waiting off
**21*#Enable call forwarding for calls to .
##21#Switch off call forwarding automatically
*#21#Call forwarding status query for calls
*21#Switch on call forwarding automatically
**62*#Activate call forwarding if not reachable on specified .
##62#Switch off call forwarding in case of unreachability
*62#Switch on call forwarding in case of unreachability
*#62#Status query of call forwarding in case of unavailability
**61*#Activate call forwarding after the 5th ring to specified number
**61**Activate call forwarding after specified time to specified number
##61#Switch off call forwarding after a certain time (after 5 rings)
*61#Switch on call forwarding after a certain time
*#61#Call forwarding status query
**67*#Activate call forwarding to specified number in case of busy line
##67#Deactivating call forwarding when busy
*67#Activate call forwarding when busy
*#67#Status query of call forwarding in busy mode
##002#Switch off all call forwarding automatically
*002#Switch on all call forwarding automatically
##004#Switch off all conditional call forwarding (busy, after 5th ring, unreachable).
*004#Switch on all conditional call forwarding


Apple: List of USSD Codes

Let’s start with the USSD codes for all Apple iPhone and iPad devices. Below you can see all the mobile codes for all iOS devices.

USSD CodesFunctionality
*3001#12345#*Field test mode
*#5005*7672#Display SMSC number
*#746025625#SIM Clock Stop (power is only consumed when you actually use the SIM card)
*3370#Activate EFR (Enhanced Full Rate) mode, increases voice quality during calls, battery power decreases
#3370#Disable EFR mode
*4720#Enable HFR (Half Full Rate) mode, reduces voice quality, battery power increases
#4720#Disable HFR mode
*#5005*86#Show mailbox settings
*646#Query current call volume

Samsung: List of USSD Codes

Even the Galaxy from smartphone manufacturer Samsung has its own specific cell phone codes in addition to the generally valid GSM codes.

USSD CodesFunctionality
*#0*#comprehensive test menu
*#1111#Software version
*#1234#Firmware version
*#2222#Hardware version
*#0228#Battery status and temperature
*#8999*8376263#Details about camera, product code, etc.
#*5376#Delete all SMS
*#9090#Service mode UART/USB (service diagnosis configuration)
*#0808#USB settings
*#34971539#Check and display camera firmware


Huawei: List of USSD Codes

The manufacturer Huawei also has its own cell phone codes, which you can see in the table below.


USSD CodesFunctionality
*#*#0000#*#*Display model number, hardware version and IMEI number
*#*#6130#*#*Test menu (usage statistics, phone information)
*#*#2846579#*#*Service menu (e.g. manual upgrades and downgrades)
*#*#1357946#*#*Product code and serial number

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About The Author
Meet Emily Chen, a travel writer and eSIM enthusiast. Emily’s love for exploring new places has taken her all over the world. She now shares her experiences and tips for staying connected while traveling through her writing on eSIMradar.
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