Depending on the province where you have incurred the expense, whether businesses are required to collect HST or GST, you would claim the expense in the column that relates to the type of taxes that are paid. It is possible to use all three columns, for example you incurred fuel expenses in one province that collects GST and more in another that collects HST. The total expense would be reported in each respected column, for example ($100 + $5 GST) = $105 to report in the GST column, and ($100 + $13) = $113 to report in the HST column.
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