Sales tax in Ontario
Ontario charges 13% HST — one blended tax, one remittance. Essentials, point-of-sale rebates, and selling in and out of the province.
One tax, mercifully
Ontario harmonized: 13% HST on most sales, one line on the receipt, one remittance to the CRA. Input credits work on the full 13%.
The rebate quirks
Certain items get point-of-sale relief of the provincial portion — children's clothing, books, prepared food under $4 among them — effectively charging 5% at the till. Category-level tax rules handle these; hand-toggling does not, reliably.
In SeroBooks
Ontario destinations compute 13% (or the relieved rate by category); the engine treats HST as its own kind, never as 'GST plus something'.
One rate, two governments behind it
Ontario harmonizes its provincial portion with the federal tax into a single rate charged to the customer. That is genuinely simpler at the counter — but the revenue is still split between two governments, and certain items carry point-of-sale rebates that make the effective treatment differ from the headline rate.
Books that record the combined figure alone lose the ability to explain any of that later.
Selling out of province from Ontario
Ontario businesses shipping across the country charge by place of supply, which means encountering separate provincial taxes and different harmonized rates on the same day. For a marketplace seller this is the normal case rather than the exception.
The destination matrix handles it per line, so the rate follows the buyer without anyone maintaining a lookup table.
How SeroBooks applies this
Tax is decided per line, not per invoice. Each line's treatment comes from the product's tax category and the place of supply, so a GST-only item and a GST-plus-provincial item sit on the same sale without anyone thinking about it. Combined rates split into their federal and provincial halves in the ledger — one payable account per tax actually levied — which is what lets a return be filed from the books rather than rebuilt in a spreadsheet.
The Tax report then reads that same ledger for any period: taxable sales by rate with the base for each, zero-rated sales counted rather than dropped, credit notes netted, and a self-check against the sales ledger that says so out loud when the two disagree. Input tax credits accrue from purchase documents as they are entered.
Tax handled per line, per province, automatically.
The place-of-supply engine inside SeroBooks does this all day.