HST/GST Filing Deadlines for Ontario Small Businesses: Monthly vs Quarterly vs Annual

If you're registered for HST/GST in Ontario, the #1 way businesses get into trouble is simple: they don't know their reporting period (monthly, quarterly, or annual), and they mix up filing vs payment deadlines.

This post gives you a clear, practical breakdown so you can stay on time without guessing.

Step 1: Confirm your HST/GST reporting period

Your deadlines depend on your CRA reporting period:

• Monthly
• Quarterly
• Annual

Don't assume. Confirm it inside CRA My Business Account (HST/GST details).

Step 2: Monthly filing (Ontario) — what it usually means

If you're a monthly filer, you generally need to:

• file your HST/GST return 1 month after the end of each reporting month
• pay any amount owing by the same deadline

Simple way to think about it: Month ends → next month you file/pay.

Monthly filing can be good if you have higher volume and want tighter cash-flow control, but it requires consistent bookkeeping.

Step 3: Quarterly filing (Ontario) — what it usually means

If you're a quarterly filer, you generally need to:

• file your return 1 month after the end of the quarter
• pay any amount owing by the same deadline

Quarterly filing is common for small businesses because it reduces admin work, but you still need a routine to track:

• HST collected on sales
• HST paid on expenses (ITCs)

Step 4: Annual filing (Ontario) — what it usually means

If you're an annual filer, you file once per year, but you still need to track HST all year.

Important: in some cases, the payment deadline can be earlier than the filing deadline. That's why annual filers should be extra careful and confirm exact dates in CRA My Business Account.

Filing deadline vs payment deadline (don't mix these up)

Two different things:

• Filing deadline: when the return must be submitted
• Payment deadline: when the money must be paid

If you file but pay late (or pay but file late), CRA can still charge penalties/interest depending on the situation.

What to prepare before you file (Ontario checklist)

Before filing your HST/GST return, make sure you have:

• Total sales/revenue for the period
• HST collected on taxable sales
• Expense totals with HST paid (possible ITCs)
• Receipts/invoices organized (especially higher-dollar items)
• Personal vs business spending separated (keep it clean)
• Bank and credit card accounts reconciled for the period

If you're missing receipts, don't guess. Clean it up first.

Common Ontario small business mistakes

• Not knowing their reporting period
• Waiting until the deadline week to start bookkeeping
• Claiming ITCs without proper invoices/receipts
• Mixing personal and business spending
• Filing the return but forgetting the payment
• Numbers not matching because accounts weren't reconciled

A simple routine that makes HST filing easy

If you want HST filing to feel “easy,” do this:

• Weekly: save receipts + label anything unclear
• Monthly: reconcile bank/credit cards + check HST collected vs ITCs
• Before filing: run the checklist above

This prevents last-minute panic.

FAQs