Starting May 17, 2010 NANPA introduces a new area code for the province of Ontario, Canada as a relief plan for area code 613. The new area code is 343 and it will cover th exact same region currently covered by area code 613, including these following cities: Ottawa, Kingston, Cornwall. The solution of adding an overlay code is generally preferred to the splitting of a geographic area between the old and new area code due to lower implementation costs. 10 digit dialing will be a requirement within the new overlay complex 343/613.
NANPA announcement and map of area codes 343/613 (in PDF format)