Open a separate business bank account before you send your first invoice, and run every dollar of the business through it. There is no law forcing a sole proprietor to keep a separate account, but mixing personal and business money (called commingling) makes your bookkeeping a nightmare, makes legitimate deductions almost impossible to defend in a Canada Revenue Agency (CRA) review, and, if you are incorporated, can cost you the very liability protection you incorporated for. This is the single cheapest piece of financial discipline a new tradesperson can put in place, and it pays back every tax season.
Why separation matters, even for a sole proprietor
A sole proprietor and the business are the same taxpayer, so people assume one account is fine. It is not, for three practical reasons:
- Clean records. When business income and spending sit in their own account, your bookkeeping is a single feed to reconcile. Mixed accounts force you to pick every business transaction out of your groceries and gas by hand.
- Defensible deductions. If the CRA reviews you, you have to substantiate every expense you claimed. Business spending on a dedicated account is easy to prove. Business spending buried in a personal account, with no separation, is the kind of thing reviewers disallow.
- Knowing your numbers. With one account you cannot tell profit from owner draws. A separate account shows you what the business actually earned and what you took out, which is what you base your tax set-aside and your pricing on.
Why it matters more once you incorporate
For a corporation, commingling is not just messy, it is dangerous. A corporation is a separate legal person, and the liability shield depends on you treating it that way. If you deposit corporate revenue into your personal account, or pay personal bills straight out of the corporate account, a court can decide to "pierce the corporate veil", meaning a judge treats the corporation as if it never existed and holds you personally liable for its debts and judgments. The protection you paid to set up is only as strong as your discipline in keeping the money apart. See Sole Proprietor vs Incorporation for the wider trade-off.
What commingling looks like, and how to avoid it
These are the everyday slips that blur the line. Each has a clean alternative.
- Depositing a customer cheque made out to the business into your personal account. Always deposit business income to the business account.
- Buying job materials on your personal debit card with no reimbursement record. Use the business account or card; if you must use personal funds, record it as an owner contribution and reimburse yourself cleanly.
- Paying a personal bill (your home phone, a streaming subscription) from the business account with no documentation. Pay personal costs personally, or record the draw.
- Moving money between accounts without labelling it. Every transfer should be tagged as either an "owner draw" (money out to you) or an "owner contribution" (your money in). Unlabelled transfers are what make a set of books impossible to follow.
The rule of thumb: pay yourself a regular draw or salary from the business account rather than dipping in at random, and keep personal spending on personal accounts.
Setting it up in the first week
You do not need anything fancy. The practical setup:
- Open a business chequing account on day one, before you invoice anyone. The major Canadian banks all offer business accounts, and there are lower-fee and digital options as well. Compare monthly fees and transaction limits; a high-volume trade account and a quiet one have very different costs.
- Get a business debit or credit card tied to that account, so card spending is automatically on the business side.
- Link accounting software to the business account from the start. Connecting a tool such as a cloud bookkeeping package to the business account lets transactions flow in automatically, which is far easier than entering them by hand at year end.
- If you are GST/HST registered, bank the tax separately. The GST/HST you collect is not your money; it is held in trust for the CRA. Many tradespeople move the tax, plus a slice for income tax and Canada Pension Plan, into a second savings account the day a payment lands, so it is never mistaken for cash flow. See Registering for GST/HST.
A simple worked routine
Say you finish a $5,000 job in Ontario and invoice $5,000 plus 13 percent HST, so $5,650 arrives. The clean routine: the full $5,650 goes into the business chequing account. You immediately move the $650 of HST into the tax savings account, plus a set-aside for income tax and Canada Pension Plan (many start at 25 to 30 percent of the net). What is left is what the business has actually earned, from which you pay a regular draw to yourself. Done every time, this keeps the trust money safe, the books clean, and the tax bill from ever being a surprise.
Common mistakes
- Running everything through a personal account. The classic first-year error. It makes deductions hard to prove and your real profit impossible to see.
- Spending the GST/HST you collected. It is trust money owed to the CRA. Bank it separately the day it lands.
- Unlabelled transfers. Every movement between personal and business should be tagged as a draw or a contribution.
- Commingling after incorporating. It can lift the corporate veil and expose you personally, undoing the point of the corporation.
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Keep reading
Need help pricing your work? Read Section 14: Pricing Your Work - day rates, job prices and how to stop underselling yourself.
Finished your apprenticeship? Read our guide: After Your Apprenticeship - the stuff nobody teaches you in college.
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