What happens if I file my HST return late?
A late HST return with a balance owing triggers a penalty of 1% of the balance plus a monthly add-on, and interest at CRA’s prescribed rate until paid.
If you file an HST return late and owe money, CRA charges a penalty built from two pieces: 1% of the balance owing, plus a quarter of that 1% for each full month late, up to twelve months. Interest at CRA’s prescribed rate runs on top, compounding daily, until the balance is cleared.
If you are owed a refund, file anyway
No balance owing generally means no late-filing penalty — but an unfiled return blocks your refund, can freeze other CRA accounts’ refunds, and puts your compliance record offside, which matters if you ever need flexibility from CRA later.
The compounding problem
Most late HST returns are late because the bookkeeping behind them is behind. One skipped quarter becomes two, the numbers get harder to reconstruct, and the penalty math grows with the balance. The fix is boring: books that are current, and returns that are prepared from them on schedule.
This is general information, not tax advice for your situation. Book a call and a Canadian accountant will give you the answer for your business.
Common questions
I can't pay the HST I owe. Should I still file on time?
Yes. Filing on time avoids the late-filing penalty even if you cannot pay in full, and CRA will set up payment arrangements. Not filing makes everything worse.
How far behind can HST filings get before it's serious?
CRA can demand a return at any time, and persistent non-filing can lead to arbitrary assessments where CRA estimates your sales for you, rarely in your favour. Two missed periods is the point to act.