A postal code (known in various countries as a post code , postcode , or ZIP code ) is a series of and/or digits appended to a postal address for the purpose of sorting mail.Postal codes are codes designating the areas that each post office serves. So it depends on where in Lebanon your letter is addressed. ( code postal liban )

Address format for Lebnon

Mr. Hassan
526 bina Street. 2nd floor

Postal Codes in Lebanon consist of 4 numbers,also consist of 8 numbers

Example :  2 0 3 8  3 0 5 4

The first four digits represent the region or postal zone,the last four digits represent the building.

Follows this links of all post offices in Lebanon, their address and their postal code.

Beirut District
Mount Lebanon 1
Mount Lebanon 2
South Lebanon
North Lebanon