Turkey
Turkey Postal Code Format Explained
Turkey postal codes have five digits, and the first two match the province number. See the structure, sample formats and common mistakes.
Updated 14 October 2026 · 3 min read
The Turkish postal code, known as posta kodu, is a five-digit number. Its first two digits give the province, and the other three digits refine the district and delivery area. It is written after the street address, usually before the district and province.
Structure of the five digits
The leading two digits match the province's administrative number, the same two-digit plate code from 01 to 81. This makes Turkish codes easy to sanity-check: if the province in an address is Istanbul and the code does not start with 34, something is wrong. The last three digits identify the district and delivery area within that province.
A code generally covers a neighbourhood, a group of neighbourhoods or a delivery zone, not a single building. Several streets share the same code, and a large district can have many.
Examples of valid format
These are format examples only, not real codes:
34000— five digits, first two digits matching Istanbul province06000— leading zero is part of the code and must be kept35000— five digits, province prefix 35
Invalid forms include 3400, 340000, 34 000 and TR-34000.
Leading zero
Provinces numbered 01 to 09 start with zero. Spreadsheets and some forms strip the leading zero and turn 06000 into 6000. Store postal codes as text rather than numbers, and check the length before submitting.
Common mistakes
- Missing leading zero for provinces such as Ankara (06).
- Mixing up province and district numbers. The first two digits are the province; do not use the district name as part of the code.
- Using the code as a location. It narrows delivery to an area, but the street and number are still required.
- Copying the code of a neighbouring neighbourhood. Even adjacent neighbourhoods can differ.
- Adding a country prefix. Domestic forms expect only the five digits.
For how to look up a code properly, see find a postal code in Turkey.
Where UPCS fits
The posta kodu helps PTT and couriers sort mail. A UPCS code of the form TR-XXXX-XXXX is separate: it marks a 3 m by 3 m spot and is not an official postal code. The Turkey overview shows how the two are used together, and the address format page shows where the postal code sits in a written address.
Frequently asked questions
What do the first two digits of a Turkish postal code mean?
They correspond to the province number, from 01 to 81. For example, a code starting with 34 belongs to Istanbul province.
Does every Turkish address need a postal code?
Most forms and shipping labels ask for it. Mail can still be delivered with a clear neighbourhood, street and number, but including the code speeds sorting.