The dialer codes, so named because they can be accessed directly from the phone's call keypad, are still a mystery to the average user, while they hold no secrets for more advanced users, who have been using them for years to access a series of test menus and advanced settings otherwise not accessible from the standard user interface.
The best known dialer code is undoubtedly the one that allows you to view the IMEI, i.e. the unique identification code that allows you to block the phone in case of loss, and is associated with the guarantee, by typing the string *#06# in the numeric keypad. Other dialer codes allow you to carry out test activities reserved for the more expert, but which can be useful if you intend, for example, to carry out diagnostic operations for a repair.
Android smartphones are famous for containing a variety of hidden features. In more recent versions, especially since Android 4.4 KitKat, the use of a large part of these codes has fallen into disuse and has been replaced by new entries in the settings, which is why, among the codes that we will list below, some will not work on board the most recent devices.
Before delving into the two main types of dialer codes, namely MMI and USSD, it is good to remember that, while some codes allow you to view useful information and change the settings of the answering machine, others can cause damage to the device if used in irresponsible way.
There are codes capable of carrying out a complete reset to the factory data or even a memory partition of the device, which we have appropriately reported, but in principle the more advanced settings are designed to be used only by the most aware and expert users in this field.
In this article we will list all the Android dialer codes, divided into the following categories:
MMI and USSD, what's the difference?
The dialer codes all seem the same at first sight: in fact, they are made up of a numeric string preceded and followed by the asterisk and pound symbols, which can be dialed directly from the smartphone call keypad without the need, at least in most cases, to perform further operations. However, they are divided into two main categories, which are quite different in nature: MMI and USSD.
MMI (Man Machine Interface)
MMI codes are part of the man-machine interface of the phone: just like the most commonly used settings, they in fact mediate the interaction between the user and the functionality of the device, with the exception that they are placed at a more hidden level than the graphical interface with which one usually comes into contact.
The MMI codes of Android smartphones include most of the dialer codes that allow you to access additional information about the device, enter test and diagnostic menus that are useful for technicians to identify problems in components such as the display or GPS and, in exceptional cases, carry out a complete reset of the smartphone.
In some rare cases, such as in OnePlus and Asus smartphones, the MMI codes can be found within the app dedicated to the calculator, with the function of accessing the test menus or simply as nice easter eggs.
USSD (Unstructured Supplementary Service Data)
USSD codes, although formatted almost identically to MMI codes, have a completely different nature: they are in fact used for communications between the smartphone and the mobile network operator to which the SIM card is associated. USSD technology, used since the dawn of mobile technologies, is a more immediate and less expensive method of communication than SMS, but with the spread of Internet-based technologies it has become largely obsolete.
Although still used in some developing countries as a means of payment, USSD technology and its associated codes have fallen out of use in most markets.
In Italy, for example, TIM customers could access their remaining credit using the code *123#, while now it is necessary to call, send an SMS or access the dedicated application. On the Italian territory the USSD codes are still used by the main operators with only one but important function: that of managing the answering machine.
Android generic codes
Test codes
Configuration codes
Developer codes
Other dialer codes
Reset codes (WARNING!)
Dialer codes from major brands
Samsung
Xiaomi
realme
OnePlus
Asus
Huawei
Motorola
HTC
Sony
Nokia
Dialer codes for Italian operators
TIM
Your mobile phone is switched off or out of coverage
You are engaged in another conversation
h4>When your phone rings but you cannot answer the call
If you want to divert all the calls you receive directly to Voicemail
Vodafone
All call forwarding to voicemail
When the phone is switched off/unreachable
When the number is busy
When you cannot or do not want to answer< /h4>When you want to divert all calls to voicemail, even when the phone is on
Iliad
WindTre
Phone off or unreachable
You cannot or do not want to answer
You are busy on another conversation
All of the above cases
All calls in arrival even when phone is on
Fastweb
Divert to answering machine
When you want to divert all calls to voicemail, even when the phone is on
Iliad
WindTre
Phone off or unreachable
You cannot or do not want to answer
You are busy on another conversation
All of the above cases
All calls in arrival even when phone is on
Fastweb
Divert to answering machine
| Activation | Deactivation | |
| Off & unreachable | *62*3730004410# Enter | ##62# Enter |
| Busy | * 67*3730004410# Enter | ##67# Enter |
| Cannot/do not want to answer | *61*3730004410# Enter | ##61# Enter |
| Always even if on | *21*3730004410# Enter | ##21# Send |
Divert to another number
| < td>Activation | Deactivation | Check service status | |
| Off & unreachable | *62*# Enter | ##62# Enter | *#62# |
| Busy | *67*# Enter | ##67# Enter | *#67# |
| Can't/unwilling to answer | *61*# Enter | ##61# Enter | *#61# |
| Always even if on | *21*# Enter | ##21# Enter | *#21# | < /tr>