Its overlay area code is the 289 area code. It was introduced to the public in the middle of 2001. The first Mississauga (Malton) area code was all used up in the later months of 2005, thus the 289 area code will become the area code of phone numbers that will be given starting from that time onwards.
Direct inward dialing (DID), also called direct dial-in (DDI) in Europe and Oceania, is a telecommunication service offered by telephone companies to subscribers who operate a private branch exchange (PBX) system.
Note: Calls to Canada, Puerto Rico, Guam, U.S. Virgin Islands, Northern Mariana Islands, and Caribbean countries listed below with an IDD prefix of 1 only require you to dial 1 + area code + number just like you call numbers within the United States. No country, city, or international access codes are required. Customers calling from the United States to a mobile number in Mexico must dial a 1 after the Mexico country code of 52 and before the 10-digit local number.