There is no area code 521 in Mexico. However, when calling a mobile phone (cellphone) in Mexico from other countries, you must insert the prefix '1' in between the country code +52 and the geographic area code.
For example, a landline in Guadalajara begins with +52 33, but a mobile from Guadalajara begins with +52 1 33.
(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.)
Area code 521 is utilized for personal communication services. It is not assigned to a geographic area. Area code 521 was officially put into service on September 21st, 2017.
Area code 521 is utilized for personal communication services. It is not assigned to a geographic area. Area code 521 was officially put into service on September 21st, 2017.
Country code +52 is Mexico. Area codes in Mexico are either two digits (33 = Guadalajara, 55 = Mexico City, and 81 = Monterrey) or three digits (200 - 999). However, to dial a mobile phone in Mexico, you must insert a '1' between the country code and the area code. Thus, a number beginning with +52 1 is a mobile in Mexico.
Area code 521 is utilized for personal communication services. It is not assigned to a geographic area. Area code 521 was officially put into service on September 21st, 2017.
The country code and area code of Zliten, Libya is 218, (0)521.
The country code and area code of Steenwijk, Netherlands is 31, (0)521.
The country code and area code of Rangpur, Bangladesh is 880, (0)521.
The country code and area code of Bielefeld, Germany is 49, (0)521.
The country code and area code of VÌ_nersborg, Sweden is 46, (0)521.
Country code +49 is Germany; area code +49 521 (or 0521 within Germany) is Bielefeld, Nordrhein-Westfalen.
The country code and area code of Coronel Oviedo, Paraguay is 595, (0)521.
The country code and area code of El Fao, Sudan is 249, (0)521.