GSM Codes Dictionary — — IMEI, Forwarding & Operator Codes

How to use GSM codes

Codes come in two forms: strings starting with '*' and '#' are typed on the dialer and 'called' (e.g. *#06#); the network answers on-screen instantly. Strings like 'KALAN → 2200' are SMS codes: type the word into a message and send it to the given number. Both run on the network side — no internet needed.

Codes fall into three families: universal GSM-standard codes (IMEI, forwarding, waiting), operator service codes (quota, invoices, packages), and device-vendor service menus (Android *#*#4636#*#*). If a code fails, first make sure you've picked the right family: operator codes work only on that operator's line.

The dictionary below filters codes by group and copies them with one tap. Operator short numbers and some behaviors vary by plan/region; for critical actions use your operator's official app as the verification tool.

Call forwarding codes — the most-needed family

Forwarding codes follow a simple grammar: strings like *#21# starting with '*#' show status, strings like ##21# starting with '##' disable, and strings like **21* enable. There are four scenarios: unconditional (21), no-answer (61), unreachable (62) and busy (67). The standard first step of any forwarding cleanup is ##002# — it disables all four at once.

To quickly check whether your phone has been forwarded to someone else, dial *#21#, *#61#, *#62# and *#67# in order; if all return 'not active', you're clean. Finish by dialing ##002# to be sure. For users worried about 'is my phone tapped', this is a safe, network-level verification.

Operator short codes and SMS numbers

These codes are verified from the operators' official support pages: Turkcell documents the KALAN→2200 SMS and the *100# dial-in; Türk Telekom documents the KALAN, INTERNET and GUNCEL services on 5555. On Vodafone, remaining usage is primarily shown in the 'Vodafone Yanımda' app; the SMS service can vary by plan.

Using the codes — step by step

1. 1

   Find the code in the right group

   Pick your group in the dictionary: forwarding/waiting/privacy under 'Universal', quota/invoice under your operator. Choosing the wrong group is the number-one cause of 'invalid MMI' errors.

2. 2

   Tap the copy button

   The row's copy button puts the code on your clipboard. In USSD codes the * and # characters are critical; manual typing raises the error rate.

3. 3

   Paste on the dialer and call

   USSD codes run instantly with the answer on-screen. For SMS codes open the messaging app, use the body word and the target number.

4. 4

   Verify the answer and repeat if needed

   If forwarding status reads 'active', run the '##' version to cancel. Quota queries answer by SMS within seconds.

These steps are marked with HowTo schema

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Source and freshness

Universal codes (IMEI, forwarding, waiting, privacy) follow the GSMA GSM standard and behave identically on every operator. Operator codes are written from the operators' official support pages; campaign- and package-specific short codes (e.g. package purchases) change frequently and are deliberately excluded — only permanent, verifiable codes are listed.

If a code fails, your operator's official app is the most current verification tool. The page is reviewed regularly and code changes are updated.

Frequently Asked Questions