Toronto, Ontario · EST/EDT (UTC-5) · Canada
Toronto and surrounding Greater Toronto Area (overlay with 416/647)
Third Toronto overlay (after 416 and 647), introduced in 2013 to meet growing demand in the Greater Toronto Area. Primarily assigned to mobile and VoIP numbers. The GTA is Canada's economic hub — home to five of Canada's six largest banks, the TSX, and major tech and media companies. 437 numbers are common among newer businesses and younger residents.
Dial 1 + 437 + 7-digit number for calls from outside the area. 10-digit dialing is mandatory in this area due to overlay codes.
From outside Canada: dial your country's exit code + 1 + 437 + number. From most countries, the format is +1-437-XXX-XXXX.
Area code 437 is in EST/EDT (UTC-5). Business hours are typically 9:00 AM – 5:00 PM local time. Remember that clocks shift during DST (March–November).
While (437) is a legitimate area code, scammers can spoof any number. Never share personal info with unknown callers. Verify by calling the organization directly.
Area code data sourced from NANPA. Timezone data from IANA Time Zone Database. Last updated March 2026.