More than 800 million of the $20 green paper bills are in circulation, the country's most-used currency, the Toronto Sun said.
Bank of Canada spokeswoman Julie Girard told the Sun the plastic-based bills would be phased in over a 2-year span to allow "people to be comfortable with them."
She said banks and owners and operators of some 500,000 automated banking machines were given notice of the transition to plastic-based bills in 2009.
Last year, plasticized $50 and $100 bills went into circulation. By the end of 2013, the central bank will begin introducing similar $10 and $5 bills, the report said.