According to the Canada Revenue Agency (CRA),

"What is a Canada training credit limit? - Starting in 2019, an eligible individual will be able to accumulate $250 in each year (provided the individual satisfies all the conditions stated in Q10), up to a maximum of $5,000 in a lifetime. The Canada training credit limit for a year is equal to their Canada training credit limit for the previous year minus any Canada training credit claimed in the previous year plus the annual accumulation of $250 in the previous year."

The Canada Training Credit is a refundable tax credit that you would get as a deduction if you satisfy all the necessary conditions. You can still have a limit, even if you are not claiming the credit.

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