What is the country and city code of Dubai?

The telephone country code for United Arab Emirates is +971. The area code for Dubai, including Ajman, is +971 4.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)