A monthly bookkeeping checklist for Ontario sole proprietors: reconcile accounts, track HST, receipts, tax deadlines, and avoid CRA mistakes.
You sent an invoice, paid a bill and checked your bank balance. Does that mean your books are ready for tax time? Not quite. A few simple checks each month can prevent a stressful year-end.
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What Is Monthly Bookkeeping for an Ontario Small Business?
Bookkeeping means recording the money your business earns, spends, owes and is owed. A bank balance only tells you how much cash is in the account. It does not tell you whether customers still owe you money, whether a bill was missed or how much sales tax you may have to send to the CRA.
Which Bookkeeping Tasks Apply to Your Business?
Find the situation closest to yours below. The answer explains the usual starting point; the detailed rules and exceptions come later.
Your situation | What it means | What to do next |
You received a customer payment | Match it to the correct invoice so income is not counted twice. | Check the invoice and bank deposit. |
You paid a business bill | Record the expense in the right category and save the receipt. | Check whether HST was charged. |
A bank balance looks correct | That does not prove every transaction is recorded. | Compare each bank line with your books. |
You collect HST | Some of the money in your account may belong to the CRA. | Keep sales tax separate from profit. |
Example: Reconciling an Invoice and Bank Deposit
Imagine a Toronto consultant bills $5,000 in December but receives only $2,000 by year-end. The business may have earned more than the cash received, depending on its required accounting method. A monthly review shows both the unpaid customer amount and what is in the bank; looking at deposits alone misses the difference.
How to Complete Your Monthly Bookkeeping Checklist
Step 1: Collect invoices, receipts and bank statements for the month.
Step 2: Match every deposit and withdrawal to a document.
Step 3: Review unpaid customer invoices, unpaid supplier bills and HST.
Step 4: Fix missing or duplicate entries, then save a month-end report.
Basic Bookkeeping Terms Explained
Reconciliation: Checking that your bookkeeping agrees with the bank or another record.
Accounts receivable: Money customers still owe your business.
Profit: Income minus eligible expenses; it is not the same as cash in the bank.
Common Bookkeeping Mistakes and Extra Checks
Start with the right distinction: cash flow, profit and tax
Money in the bank is not the same as taxable business profit. A deposit might be customer revenue, a loan, a transfer between your own accounts, or HST collected on behalf of the government. Similarly, a payment might be an ordinary business expense, an equipment purchase, a personal draw, or a tax remittance. Assign the correct category before deciding whether it is deductible.
Most unincorporated businesses calculate business income using the accrual method, although limited exceptions exist. This means you may need to record amounts earned or incurred even before payment. Check which accounting method applies to your circumstances before relying only on bank deposits and withdrawals.
The monthly close: a practical 12-step checklist
1. Collect every source document
Gather sales invoices, customer payment confirmations, supplier bills, credit-card statements, banking records, e-transfer details, payment-platform reports, refund notices, mileage logs, and expense receipts. Save documents in a predictable folder structure such as year, month, and category. A card statement alone often does not show what was actually purchased or whether HST was charged.
2. Reconcile every bank and credit-card account
Match the accounting ledger to bank and card statements, including merchant processing fees, service charges, refunds, interest, and transactions near month-end. Investigate unexplained differences instead of entering a balancing adjustment merely to make the totals agree.
3. Match deposits to invoices and payment processors
Stripe, Square, PayPal and other platforms may deposit net proceeds after subtracting fees or refunds. For example, a $1,000 customer payment with a $30 processing fee is not automatically $970 of sales. Record the gross sale and separately classify the $30 fee, subject to the relevant accounting and tax treatment. Identify sales taxes separately where applicable.
4. Review unpaid invoices and overdue customers
Maintain a list of accounts receivable and follow up on late payments. Review credit notes, disputed balances, and genuinely uncollectible amounts. Do not write off an unpaid invoice as a bad debt without considering the conditions for the relevant tax treatment.
5. Review supplier bills and unpaid expenses
Check whether expenses relate to the business and the correct period. Identify bills still outstanding, duplicate invoices, prepayments and deposits. A personal purchase does not become deductible merely because it was paid from the business bank account.
6. Separate owner draws, contributions and business costs
For a sole proprietorship, moving money to your personal account is generally an owner draw, not a business wage expense. Money you put into the business is not automatically sales revenue. Corporations work differently: shareholder loans, salaries and dividends require their own records and analysis.
7. Review HST status and tax coding
Ask whether the business is required to register for GST/HST, has voluntarily registered, or makes supplies subject to a special rule. The ordinary small-supplier threshold is generally $30,000 of worldwide taxable supplies over a single calendar quarter or four consecutive calendar quarters, subject to exceptions and detailed timing rules. Registered businesses generally need to track tax collected and eligible input tax credits, not simply multiply all bank deposits by Ontario's 13% HST rate. Zero-rated, exempt, out-of-province and cross-border transactions require special care.
8. Record mileage and shared-use expenses
If you use a personal vehicle for business, record trip date, purpose, distance and total annual kilometres. For a home office, maintain a defensible calculation of business-use area and relevant expenses. Mixed personal/business phone, internet, meal and travel charges need a reasonable allocation. The specific deduction limits vary by expense type.
9. Identify equipment and major purchases
A laptop, camera, furniture or other long-lived asset may be capital property rather than an immediately deductible routine expense. Tax depreciation is handled through capital cost allowance, with classes and special rules. Keep purchase documents and dates; do not automatically expense every large purchase in full.
10. Check payroll and contractors
If you have staff, reconcile gross pay, net pay, source deductions, employer contributions and remittances. If you hire contractors, preserve contracts, invoices and payment history. Worker classification depends on the facts of the relationship, not just what the contract calls the worker. Do not assume every contractor payment requires the same reporting slip.
11. Review taxes, instalments and upcoming deadlines
Keep GST/HST filing and payment dates, payroll remittance dates, income-tax instalments, T-slip deadlines and annual return dates in a calendar. These deadlines vary with registration, filing frequency, entity type and tax year. Sole proprietors can have different filing and payment deadlines for personal income tax; do not equate an extended filing deadline with an extension to pay tax owing.
12. Close and explain the month
Review a profit-and-loss statement, balance sheet, cash position, tax payable balances, receivables and payables. Compare revenue and expenses with prior months. Write a short note explaining unusual changes while memories and documents are fresh. Save a read-only monthly report and backup of supporting records.
What a simple monthly bookkeeping pack should contain
Reconciled bank and credit-card statements, with unresolved items identified.
Income report showing gross sales, refunds, fees and tax collected where relevant.
Expense report with receipts and business-purpose notes.
Accounts receivable and payable lists.
GST/HST summary and remittance dates if registered.
Vehicle, home-office and equipment registers where relevant.
A tax-deadline calendar and a short exception log.
Four examples that often cause expensive mistakes
Example A: client reimburses your costs
If a client pays you $500 plus a $75 reimbursement, do not automatically exclude the reimbursement from business revenue. Whether it is your revenue, the client's disbursement, or otherwise treated depends on the agreement and the underlying facts. Check HST treatment as well.
Example B: you pay a business bill personally
The expense may still be relevant to the business, but it needs documentary support and a correct owner-contribution or reimbursement entry. Without that entry, the bank balance and profit statement may not reconcile.
Example C: you receive a deposit for work next month
The timing of income recognition and GST/HST can differ. An advance payment should not be coded automatically the same way as an ordinary completed sale without examining the facts and applicable rules.
Example D: you purchased a computer for both work and family
Keep the invoice, document business use, consider capital-asset rules and do not assume 100% deductibility. Personal use can change both income-tax deductions and GST/HST input-tax-credit eligibility.
How long should records be kept in Canada?
CRA's general rule is to retain required books and records for six years from the end of the last tax year to which they relate. Important exceptions can extend that period, including matters involving an objection, appeal, property ownership or other continuing tax consequences. Electronic records must remain readable and accessible, with adequate backups. Do not delete records simply because a return has been assessed.
When a sole proprietor should consider professional help
Seek tailored advice if you are nearing GST/HST registration thresholds, selling internationally, carrying significant inventory, acquiring expensive equipment, hiring staff, receiving a CRA review letter, switching from sole proprietor to corporation, or managing substantial personal use of business assets. A monthly bookkeeping system is meant to make decisions clearer, not replace tax analysis.
Frequently asked questions
Can I use a spreadsheet instead of accounting software?
Yes, for a simple business if the spreadsheet accurately captures transactions, preserves supporting documents and supports reliable reconciliations. Complexity, transaction volume, inventory, employees or tax requirements may make dedicated software more practical.
Is my bank statement enough proof of an expense?
Not always. CRA may need to see what was purchased, from whom, when, for how much, and why it relates to earning income. Retain invoices and receipts alongside proof of payment.
Do I need a separate business bank account?
Even if not legally required for every sole proprietor, separating accounts often improves bookkeeping, audit trails and cash-flow visibility. Incorporated businesses should treat the corporation as a separate legal entity.
If I earned less than $30,000, can I ignore HST?
No. Threshold calculations have specific timing and supply rules; some businesses register voluntarily or face exceptions. You also need to distinguish taxable, zero-rated and exempt supplies and check whether other jurisdictions' rules apply.
Need help applying these rules?
Presyz provides accounting and taxation services in Toronto. If your situation involves competing tax choices, missing records, or a complex transaction, contact Presyz through the website to discuss your circumstances before acting.
If you are deciding whether to stay self-employed or incorporate, read our Ontario sole proprietorship versus corporation comparison for differences in income-tax filing, HST accounts and business bookkeeping.
Official sources and further reading
CRA — Keeping records.
CRA — Business expenses.
CRA — GST/HST small supplier rules.
Reviewed for publication planning: October 2026. This is general Canadian information with an Ontario focus; it is not individualized accounting, tax or legal advice. Confirm current CRA guidance when acting.
General educational information, not individualized tax, legal or financial advice. Verify current CRA requirements.