TL;DR: The most common e-commerce bookkeeping mistake in Canada is recording Shopify or Amazon deposits as revenue. Those deposits are a net number — sales minus fees, refunds, and adjustments, often spanning parts of two months — and booking them as sales quietly corrupts your revenue, margins, and HST filings all at once. The fix is a proper channel-to-books pipeline (tools like A2X into QuickBooks Online), real inventory and COGS accounting, and HST tracked by province. Get that right and your numbers become something you can actually run the business on.
Here’s a test. Open your books and compare last month’s recorded revenue to what your Shopify dashboard says you sold. If those numbers match, either your bookkeeping is set up properly — or nobody’s looked closely enough to notice they shouldn’t match at all.
For most e-commerce businesses we review, the books are built on bank deposits. Money lands from Shopify Payments, it gets coded to “Sales,” and everyone moves on. It feels reasonable. It’s also wrong in about four different ways at once, and past a certain size those errors start costing real money.
A payout is not a sale
A Shopify or Amazon payout is a settlement, not revenue. Inside a single deposit you’ll find:
- Gross sales from some range of dates
- Minus processing fees (and on Amazon: referral fees, FBA fees, storage fees, advertising)
- Minus refunds and chargebacks, which may relate to sales from previous periods
- Plus/minus adjustments, reserves, and the occasional mystery line
Book the deposit as sales and you’ve understated revenue, buried your fees (which are a real, growing cost you should be watching), and mixed multiple periods into one number. Your gross margin is now wrong. Your revenue trend is wrong. And because HST is calculated on actual sales — not on net deposits — your tax filings are built on the wrong base too.
The problem compounds across channels. A business selling on Shopify, Amazon, and Etsy has three settlement systems, three fee structures, and three timing patterns, all flowing into one bank account. Deposit-based books turn that into soup.
The fix: a proper channel-to-books pipeline
This is a solved problem, and the solution isn’t heroic manual work — it’s the right connection between your sales channels and your accounting file.
Tools like A2X sit between your channels (Shopify, Amazon, and others) and QuickBooks Online, and post summarized journal entries that break every payout into its real components: gross sales, discounts, refunds, fees, and taxes, matched to the periods they belong to. Each deposit then reconciles cleanly against the entry, to the penny.
What this gets you:
- True revenue by channel, matching what actually sold
- Fees visible as their own expense lines — so when Amazon’s take creeps from 15% to 22% of a product’s price, you see it happen instead of discovering it in a bad year
- Refunds tracked separately — a rising refund rate is an early product-quality or listing-accuracy signal, not noise
- Clean HST data — tax collected recorded from the source, not reverse-engineered from deposits
We connect stacks like Shopify, A2X, and QBO for clients regularly, and the before/after on the financials is usually dramatic. Not because anything was dishonest before — because the structure finally matches how the money actually moves.
Inventory is where e-commerce profits hide (or die)
The second structural problem: expensing inventory when you buy it.
If you purchase $80,000 of stock in March and expense it that month, March looks terrible and the following months look artificially great. Your monthly profit becomes a chart of your purchasing decisions, not your business performance.
Proper accounting puts purchases on the balance sheet as inventory, then releases them to cost of goods sold as items actually sell. That’s what makes gross margin — the single most important number in an e-commerce business — real. And landed cost matters: freight, duties, and import brokerage belong in your product cost, not in a general expense account. A product with a healthy margin at invoice cost can be a money-loser at landed cost, and plenty of sellers scale exactly those SKUs because their books can’t tell the difference.
At minimum, you need a monthly inventory position and a COGS calculation. Growing past that, an inventory system that syncs with your channels stops the guesswork entirely.
HST for e-commerce: it’s about where your buyer is
Canadian sales tax for online sellers runs on place-of-supply rules: you generally charge tax based on your customer’s province, not yours. An Ontario seller charges 13% HST to an Ontario buyer, 5% GST to an Alberta buyer, and 15% to a buyer in Nova Scotia — and some provinces (BC, Saskatchewan, Manitoba, Quebec) run their own separate provincial systems with their own registration rules once you have customers there.
Three things e-commerce owners routinely get wrong:
- Registering late. Past $30,000 in taxable sales over four consecutive quarters, registration is mandatory. Most serious sellers should register before that — you can’t claim input tax credits on your costs until you do.
- Assuming the marketplace handles it. Marketplace facilitator rules mean Amazon collects and remits on some sales in some situations — but not on your Shopify store, and the rules differ by province and situation. “Amazon deals with the tax” is not a filing position.
- Filing from deposit-based books. If revenue is wrong, HST is wrong. Under-remit and you’re building an audit liability with interest; over-remit and you’re donating margin.
And if you sell into the US, individual states have their own economic nexus thresholds for sales tax — a separate problem, but one to get ahead of before a state gets ahead of you.
What good e-commerce books actually look like
Pulled together, a properly set up e-commerce accounting stack gives you a monthly picture that answers real questions:
- Revenue by channel, gross and net of refunds
- Channel fees as a visible, trended cost
- True gross margin by month — with landed-cost COGS
- Inventory position, so cash decisions account for what’s on the shelf and on the water
- HST collected and owed by jurisdiction, ready to file
- Payouts that reconcile to the penny, every month
That’s not an accounting luxury. Ad spend decisions, SKU decisions, reorder decisions, and pricing decisions all depend on those numbers being real. E-commerce is a thin-margin, fast-feedback business — running it on deposit-based books means every decision is made a few degrees off course.
Frequently asked questions
Is recording Shopify deposits as revenue really that bad?
For a small hobby store, it’s survivable. Past a few hundred thousand in sales, it distorts everything downstream: revenue, margins, fee visibility, and your HST base. It’s also the single most common thing we fix when e-commerce businesses come to us.
What does A2X actually do?
It reads your channel settlements (Shopify, Amazon, etc.), breaks each payout into its components — sales, refunds, fees, taxes, by period — and posts matching entries to QuickBooks Online or Xero. Deposits then reconcile exactly, and your books show what actually happened rather than what the bank feed saw.
Do I need to charge different tax rates to customers in different provinces?
Generally yes. GST/HST is charged based on the customer’s province — 5% to 15% depending on where they are — and BC, Saskatchewan, Manitoba, and Quebec have separate provincial taxes with their own registration requirements once you’re selling meaningfully into those provinces. Your platform can calculate this automatically, but only if it’s configured correctly and your registrations are in place.
When do I have to register for GST/HST?
Registration is mandatory once you exceed $30,000 in taxable sales over four consecutive calendar quarters. Registering earlier is usually smart: it lets you claim input tax credits on inventory, software, ad spend, and other costs you’re already paying tax on.
Amazon collects tax on my sales — am I covered?
Only partially, and only in specific situations. Marketplace rules can make Amazon responsible for collecting on certain sales, but they don’t cover your own website, and they don’t eliminate your registration and filing obligations. This is worth a proper review rather than an assumption.
How should inventory purchases show up in my books?
As an asset when purchased, moving to cost of goods sold as items sell — with freight, duties, and brokerage included in product cost. Expensing purchases when paid makes your monthly profit meaningless and your gross margin unknowable.
If your payouts don’t reconcile, your margins are a guess, or HST filings are built on bank deposits, the fix is structural and it’s very doable. YBL sets up and runs e-commerce accounting stacks — Shopify, Amazon, A2X, QuickBooks Online — for Canadian sellers, with inventory and multi-province tax handled properly. If you want books you can actually run the business on, let’s talk.