As per the Canada Revenue Agency: You may file up to 20 returns per computer or online account using NETFILE-certified tax software in Canada for each tax year. If you have not reached the 20 return limit and still need another activation code, please see our TurboTax FAQ: How do I buy more tax returns?
If you do more than 20 returns we would suggest you get ProFile where you can Efile an unlimited amount of returns.
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