Area Code
Ontario, Canada
Local Time
4:42 AM
Eastern Time
Area Code
343
State / Province
Ontario
Country
Canada
Time Zone
Eastern Time
Area code 343 covers 116 rate centers across Ontario. Rate centers are geographic areas used by telephone companies to determine local calling boundaries.
Use the E.164 format for clickable phone links (RFC 3966):
<a href="tel:+13435550100">+13435550100</a><a href="tel:+13435550199">+13435550199</a>Area code 343 is a North American Numbering Plan (NANP) telephone area code assigned to Ontario, Canada. It is one of 14 area codes serving Ontario. As population and demand for phone numbers grew, the region was divided into multiple numbering plan areas to avoid exhausting the available 7-digit number pool.
Yes. 343 is an active North American Numbering Plan (NANP) area code, currently assigned to Ontario, Canada. It is safe to answer or dial calls using this area code.
Area code 343 covers 116 rate centers across Ontario. Communities served include Adolphustown, Alexandria, Alfred, Almonte, Arden, and 111 more localities. Rate centers are the geographic building blocks telephone carriers use to determine local calling boundaries and to assign numbers when a business or individual requests a phone number in a specific city.
All numbers in the 343 area code observe Eastern Time (IANA timezone: America/New_York). Eastern Time is UTC−5 in winter (EST) and UTC−4 in summer (EDT). When placing a call to a 343 number from a different time zone, check the current local time above to avoid calling outside of business hours.
From within Ontario, dial the 7-digit local number directly if calling within the same rate center, or dial 1 + 343 + 7-digit number for long-distance calls within North America. From outside the US or Canada, dial your country's international exit code followed by 1 343 XXX XXXX. The country code for both the United States and Canada in NANP is +1.
Format 343 numbers using E.164 notation as required by RFC 3966: prefix with +1 and omit dashes and parentheses (e.g., +13435550100). This format ensures tel: links work correctly on all mobile browsers and VoIP apps. See the tel: URI formatting guide for complete examples.