Once you have investment income (like a T5), you are moved out of "Free." Deluxe is designed to unlock forms for interest, dividends, and certain credits (like donations or medical expenses).

If you only have a T5 with Box 13 (Interest from Canadian sources), Deluxe should be the end of the line for you. You shouldn't be asked to pay again unless you suddenly add a rental property or a business (T2125).

The reason the "What Deluxe covers" list didn't seem to include your specific line is likely because Intuit groups "T5, T3, and T5008" under the broad umbrella of "Investment Income and Expenses."

Hope this helps! 

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