How do you catch up on bookkeeping when you are months or years behind?

Short answer: start with what has a deadline or a penalty attached: GST/QST returns and payroll remittances, then income tax returns, oldest year first. Gather your bank and credit card statements, rebuild each month from them, attach the receipts you still have, and reconcile every account. Once the backlog is filed, switch to a monthly routine so it doesn't happen again.

First, don't panic about the size of it

Catch-up work looks huge from the outside. In practice, the bank statements already contain most of the story. Every deposit and payment is there; the job is to explain each one and attach the paper where you can.

What to gather

  • Bank and credit card statements for every month you're behind (download them while the bank still offers them online).
  • Sales invoices, platform reports (Stripe, Square, Shopify, Uber and so on) and deposit details.
  • Purchase receipts and supplier invoices, paper or digital.
  • Loan statements, lease contracts and vehicle documents.
  • Payroll records, if you have employees.
  • Any letters from the CRA or Revenu Québec, and your last filed returns.

The order we work in

  1. Letters and notices. Anything with a date on it from the CRA or Revenu Québec goes first.
  2. GST/QST returns. If you're registered, each missing period needs a return. Late returns can trigger penalties and interest.
  3. Payroll. Source deductions held back from employees belong to the government. Missing remittances are taken seriously and get fixed early.
  4. Bookkeeping, month by month, oldest first. Record transactions from the bank statements, categorize them, attach receipts, then reconcile each month before moving on.
  5. Income tax returns, once the year's books are closed: T2 and CO-17 for a corporation, T1 and TP-1 (with the business statements) for a sole proprietor.
  6. Set up the new routine, so the current year stays clean.

If your returns themselves are late, read our article on unfiled returns.

Example: a sole proprietor 18 months behind

A consultant registered for GST/QST with a quarterly filing period hasn't touched the books since the start of 2025. That's at least six quarterly GST/QST returns missing (all of 2025 and the first half of 2026), plus the 2025 income tax returns.

  1. We download 18 months of statements and import them.
  2. We rebuild each quarter, file the GST/QST returns in order, and claim the input tax credits and refunds supported by receipts.
  3. We close 2025, prepare the T1 and TP-1, then keep 2026 current month by month.

What you lose by waiting longer

Federally, most registrants must claim input tax credits by the due date of the return for the last reporting period that ends within four years after the end of the period in which the credit could first have been claimed. Revenu Québec applies the same general four-year window to QST input tax refunds. Wait too long and some credits are gone. Receipts also get harder to replace, and suppliers' old invoices disappear.

Missing receipts

Bank statements prove you paid, not what you bought. For expenses without receipts, ask suppliers for copies, use online account histories (Amazon, utilities, phone), and keep notes on what each payment was for. GST/QST credits need proper supporting documents, so missing invoices matter most there (see what an invoice must show).

Want us to take the backlog off your plate?

Book a free 30-minute session at soleraaccounting.ca/rendez-vous or call 450 612-7223. We'll look at how far behind you are, tell you what to file first, and give you a realistic plan to get current. Service in French, English and Arabic.

This article is general information, not personalized accounting or tax advice.

Frequently asked questions

Where do I start when I am years behind on bookkeeping?

Start with anything that has a deadline or penalty: notices from the CRA or Revenu Québec, missing GST/QST returns and payroll remittances. Then rebuild the books month by month, oldest first, and file the income tax returns.

Can I still claim GST input tax credits for past years?

Most registrants have about four years, counted from the end of the reporting period in which the credit could first be claimed, and Revenu Québec generally applies the same limit to QST refunds (ITRs). Older credits may be lost, which is one more reason to catch up quickly.

Can bookkeeping be rebuilt from bank statements alone?

Bank statements are the backbone of catch-up work, but they only show that you paid. You still need receipts or invoices to support expenses and GST/QST credits, so gather copies wherever you can.

Sources

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