Phone area codes for Markham, ON
2 active area codes · Eastern Time (EST/EDT, UTC-5/-4) · population 338,503.
Markham is a major suburb in York Region and one of the most ethnically diverse cities in Canada, with a strong technology sector.
Area codes serving Markham
Dialling from and to Markham
Because Markham sits inside an overlay region with 2 overlapping area codes, callers must always dial 10 digits — even for calls between two phones on the same street. From outside Canada and the United States, dial your international access prefix, then +1, then the 10-digit number.
Mobile carriers in Markham typically issue numbers from whichever overlay code is currently being released by the NANP relief plan. As a result, two members of the same household frequently carry numbers from two different area codes — for example a long-time resident with an original-assignment number and a newer subscriber with an overlay number.
Major carriers serving Markham
About Markham, Ontario
Markham is located in Ontario, Canada. Markham is a major suburb in York Region and one of the most ethnically diverse cities in Canada, with a strong technology sector. The city falls within the Eastern Time (EST/EDT, UTC-5/-4) time zone.
Numbers issued to subscribers in Markham can come from any of the area codes assigned to the surrounding numbering plan area: 905, 289. With number portability now standard across all Canadian carriers, the area code attached to a Markham number tells you only where that number was first issued — not who currently carries it or where the device is physically located.
If you are trying to identify a recent call from 905 or 289, the caller is most likely either based in Markham or another community within the same NPA, has previously held a number issued in this area, or — in the case of telemarketing and scam calls — is spoofing a local prefix to increase the chance you pick up.