The short form of Unstructured Supplementary Service Data, USSD is a real-time interaction service allowing businesses to send & display text messages on user’s phone. Mobile USSD codes or commands are a set of characters available on a mobile phone.
This Global System for Mobile Communications (GSM) resembles an SMS. The length of this message ranges to 182 characters and connects the phone with a network or server. There’s a long list of USSD codes, and they can be used for multiple purposes like mobile payment services, location-based services, callback services, Wireless Application Protocol (WAP), and menu-based information services.
USSD lets users establish real-time connections, unlike an SMS, i.e., it ensures two-way communication as long as the line stays open. Also, these communications are instantaneous.
History of USSD code
In 1983, the European Union started planning the digital cellular voice communication standard for EU countries. In 1987, they devised a standard called Global System for Mobile Communications (GSM).
A year later, the European Commission – a body managing EU trade & business – established the European Telecommunications Standards Institute (ETSI). Its core function was to collect and regulate the information & communication technology in its member states.
In 1997, ETSI was responsible for laying the foundation of USSD technology. Two of its senior engineers published a document called GSM 02.90 addressing a protocol facilitating technical communication amongst mobile network operators’ systems and users’ mobile devices.
After some years, the mobile phone industry gained popularity. The engineers then developed a USSD protocol from the recommendations already published GSM 02.90. This protocol facilitated communication between a network operator’s system and the user’s mobile.
In the first few years, the USSD protocol was limited to queries sent from user’s mobile to the network operator’s system regarding airtime buying, checking balance, etc.
How does USSD work?
Usually, a USSD works by sending a query from the user’s phone requesting checking bank balance or activating a package. After the request is generated, the USSD gateway transfers it to the network’s USSD application, and then a response is generated.
As the network or bank responds, the response travels through the USSD gateway to the user’s mobile screen displaying the response content. Usually, the response containing 182 characters is based on an easy-to-display format. The transfer of information is initiated by dialing specific mobile USSD codes.
It is worth noting that USSD applications run on all networks and not on user’s mobile phones. You don’t need to install them on the phone. It is quite beneficial for users having feature phones that don’t have large storage capacity. The moment a user gets connected to a network, they can access the USSD apps.
Applications of USSD
Below mentioned are the several purposes for which USSD codes are used.
Mobile Banking
USSD codes for banking work on any phone, including feature phones. So, anybody can take advantage of these USSD codes, ask for information, and generate queries regarding their bank accounts. No internet is required, unlike banking apps that work with the internet and can be installed on smartphones only.
Network configuration and requests
USSD is a convenient way for network configuration of a mobile phone. It also offers the user a menu of service options from which they can request account balance, buy airtime, or accomplish any other simple task easily from the comfort of their home or office.
Customer update requests
Businesses can leverage USSD by linking it with enterprise resource planning (ERP) and customer relationship management (CRM) if they require updated customer relationships. They do it to enhance their customer service and achieve better data accuracy.
Marketing surveys
Businesses also generate USSD codes for marketing purposes. We’ve seen many organisations asking customers for marketing surveys. Their end users respond to these surveys meaning businesses and organisations get accurate customer data and honest feedback in real time. They can use this data to personalise and improve their services.
Callback services
Insurance corporations and other financial companies benefit from USSD codes to know customers’ interests regarding their services. They use these codes to enable potential customers to request callbacks regarding additional information about their offers or to get these services.
Order confirmations
Although there are apps for communication between vendors and customers and tracking orders, vendors like restaurants and electronics companies can use USSD codes for two-way communication. This quick method will help both parties, i.e., customers placing orders and expecting it to be delivered soon and vendors informing them of order dispatch and when to expect it.
Coupons & vouchers
Retailers and businesses can communicate their discounted offers & services to their clientele through USSD codes. They can also use this method to send them coupons and vouchers to enhance their sales.
USSD payments
USSD codes have been making online payments easy for a long time now. The process of sending payments is done by sending a text message to the service provider. Once the vendor receives it, they charge the product/service amount through an online system or add the amount to the user’s phone bill.
Then, the product or service is provided, and the money is transferred to the vendor’s account. Multimedia Messaging Service (MMS) often assists the purchase of digital items. The merchant can send the files to the buyer using the messaging service. If they’ve purchased a physical item, the business can send them the receipt via SMS or MMS. A high percentage of purchases done through USSD happen in Asia and Europe.
Technical details
USSD means real-time or instant messaging, and all phones come with USSD capability. Unlike SMS, which comes with store-and-forward capability, the USSD protocol offers direct communication. USSD services are based on GSM network architecture. When a user dials a specific code, it sparks an event with a USSD app on the mobile network.
The network node can be anything like a visitor location register, home location register, mobile switching centre, or any other network entity. This could also include an application platform that can access the designated USSD service. USSD enables interaction between users and operator-defined applications without the users needing to know the underlying technical details.
Typically, a mobile USSD code starts with an asterisk (*) and ends with a hashtag (#). The middle part is usually digits, making commands or data. Numbers between the (*) and (#) can also be separated by more asterisks.
Benefits of USSD
Mobile USSD codes come with several benefits. Some of the salient ones are mentioned below.
- USSD doesn’t need an internet connection to work.
- Lowers operational costs when performing as a self-service application for users.
- Businesses end up getting happy, loyal, and satisfied customers when they have the option to serve themselves.
- USSD codes work with every mobile phone.
- They bring in the convenience factor as they work globally.
- Provide real-time interaction.
- Quick, simple, and intuitive menu.
- Up to seven times quicker than SMS that work on store-and-forward model.
Differences between SS codes, MMI and USSD
Any code dialed on the mobile keypad that starts with an asterisk (*) and ends with a hashtag (#) is known as MMI or man-machine interface code. These codes look similar but fall in different groups and serve multiple purposes.
Some of these codes are sent to the SIM; some are used on the device, while others are sent to the network to request services or information.
Let’s now go through the different types of MMI codes.
USSD codes
If someone enters a code ending with a hashtag (#) and presses send, however, if the code gets rejected by the phone’s MMI interpreter, it then goes to the network verbatim to see if it accepts it. One common scenario is where a code for prepaid cards is entered to check phone balance. Many networks have a code like *#100#. But it is up to the network to decide which code to use if it isn’t taken.
Hence, if you dial *43# and send or *44# and send, it would be taken as two different codes and serve you with two different results. The network will process and accept the first code to enable call waiting on Android. While the second after processing may return with an error, meaning it is not the correct code.
Supplementary service (SS) codes
These codes are dedicated to call forwarding or number presentation. For example, if a user types *21*987654321# on the dial pad and presses call, they want the network to forward all incoming calls to the phone number 987654321. It is important to note that this number isn’t sent directly to the operator. Instead, the phone interprets it, which constructs an Abstract Syntax Notation One (ASN.1) for the operator.
Supplementary codes are hardcoded into every GSM, UMTS, and LTE device worldwide. They cannot be altered by any network.
Manufacturer-defined MMI codes
MMI codes are built by the manufacturers for activating different service menus or to reset devices, etc. Just like USSD and Supplementary codes, these specific to phone model codes also include * and #.
Now, what makes the MMI codes different from USSD and SS is that these aren’t sent to the network. There’s no need to press the send button after entering the code. These codes are executed once the user enters the last digit.
Every GSM/UMTS/LTE device manufacturer must implement *#06# as this code returns with the device’s IMEI (International Mobile Equipment Identifier).
Android USSD codes and their functions
Some of the most common USSD or secret codes for quick information or menus are as follows:
| View the IMEI number | *#06# |
| Check SAR (Specific Absorption Rate) Level | *#07# |
| Perform GPS System Test | *#*#1472365#*#* |
| Do a Touchscreen Test | *#*#2664#*#* |
| Test Wi-Fi | #*#232339#*#* |
| Enable General Test Mode | *#0*# |
| Enable Service Mode | *#*#197328640#*#* |
| Display Calendar Storage Data | *#*#225#*#* |
| View Smartphone Battery, WLAN, & other info | *#*#4636#*#* |
| View Firmware Information | *#*#4986*2650468#*#* |
| Turn Off Caller ID | *31# |
| Enable Call Waiting | *43# |
| Check Call Forwarding | *#67# |
| View Camera Information | *#*#34971539#*#* |
| Check Storage and System Details | *#3282*727336*# |
| Display MAC Address | *#*#232338#*#* |
| View Google Play Services Info | #*#426#*# |
| View Local Network Information | *3001#12345#* |
| Run a Factory Reset | *#*#7780#*#* |
| Shut Down Your Device | *#*#7594#*#* |
| Perform Factory Reset | *#*#7780#*#* |
| Reinstall Firmware | *2767*3855# |
| Find Out the SMS Message Centre Number | 5005*7672# |
|
Displays the MAC Address |
*#*#232338#*#*
|
iPhone USSD codes and their functionality
Choose from the below-mentioned iPhone USSD codes for quick information regarding your iPhone’s settings, access the hidden features, and make your iPhone perform better.
| IMEI USSD code | *#06# |
| iPhone field mode secret code | *3001#12345#* |
| iPhone call forwarding code | *#67# |
| iPhone call minutes code | *646# |
| iPhone bill balance code | *225# |
| iPhone account balance USSD code | *777# |
| iPhone configuration secret code | *# 33# |
| iPhone operator code | *#76# |
| iPhone call forwarding USSD code | *#21# |
| iPhone use of information secret code | *3282# |
| iPhone missed calls code | *#61# |
| iPhone call verification code | *#62# |
| iPhone EFR mode USSD code | *3370# |
| iPhone Outgoing Call Code | *331* |
| iPhone call waiting code | *#43# |
| iPhone activate call waiting code | *43# |
| iPhone deactivate call waiting USSD code | #43# |
| iPhone: Phone number secret code | *#31# |
| iPhone forwarding USSD code | ##002# |
| iPhone block number code | *#30# |
Conclusion
USSD (Unstructured Supplementary Service Data) offers real-time text-based communication, enabling businesses to engage users effectively.
With versatile applications like mobile banking, network configuration, and marketing surveys, USSD’s direct interaction, universal compatibility, and rapid responses prove pivotal for enhancing customer engagement and service efficiency.
From the mobile USSD code lists above, you can easily find and dial them to fulfil the required purpose quickly and more securely.
