The deadline for most Canadians was set for the end of April.
However, a spokesman for Revenue Minister Kerry-Lynne Findlay said that, due to a human error, a notification was sent last week to tax preparers indicating the deadline was May 5.
"Minister Findlay has made it clear that this incorrect information is unacceptable and therefore she has directed her officials to ensure no Canadians are penalized for the CRA's error," Carter Mann said in an email.
Canadians now have until May 5 to file their income tax return and pay any amounts they owe for 2014.
The deadline for returns for the self-employed and their spouses or common-law partners remains June 15.
Missing the tax filing deadline triggers penalties on any amounts owed to the CRA, as well as interest on the outstanding balance.
The Quebec government announced later on Tuesday it too is extending its deadline to May 5.
CRA extended the tax filing deadline for individuals to May 5 last year after the Heartbleed bug forced a five-day shutdown of its electronic services.
The CRA's affected services last year included EFILE, NETFILE, My Account, My Business Account and Represent a Client.
The Heartbleed flaw allowed the contents of a computer server's memory, including private data such as usernames, passwords and credit card numbers, to be revealed.
Some 900 social insurance numbers were stolen over a six-hour period due to the vulnerability in the CRA system.
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