If you are running a dayhome, then there is no set limit on how much you can claim for food expenses. As long as you have the receipts, and the food was for the children of the dayhome (not for you or for your family), then you can claim the amount. You would enter it as “Office stationery and supplies” in the self-employment section, as per this Canada Revenue Agency (CRA) page: Office stationery and supplies
If you have children that are cared for in a dayhome, then as long as the meals were provided as part of the childcare, then you are only limited by the total amount that you can claim for the childcare expenses deduction. In most cases the limits are:
Please see this TurboTax Article Claiming Child Care Expenses In Canada to read more about the limits and what you can claim.
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