Made a mistake on a GST/HST return? Correct the filed period without duplicating it

Establish what was submitted

Start with the GST/HST account, reporting period and original filing acknowledgement. Ask the preparer to compare the submitted figures with the corrected bookkeeping records. An error in a draft and an error in an already filed return require different follow-up.

CRA's after-filing guidance says to change an already filed return through the applicable adjustment process rather than submit a new return. It describes online adjustment for eligible periods and a written adjustment option. Review the current instructions for your situation.

Prepare a clear adjustment record

• Identify the account and exact period being corrected.
• Keep the original submission and its acknowledgement.
• List the figures that need changing and the supporting records.
• Have the preparer confirm the correction and filing method.
• Retain the adjustment confirmation and subsequent correspondence.

Label the original and revised working documents so that someone reviewing the file can tell which version was submitted at each step.

Review the payment question separately

An adjustment can raise a separate question about the account balance. Check the resulting account record with the preparer rather than treating an adjustment receipt as proof that payment has been settled. Keep any payment reference with the relevant period.

Keep the original deadline and follow-up understandable

In Compliance Calendar, use the related task's notes and confirmation references to identify the original filing and any follow-up. The calendar does not submit adjustments or calculate their tax effect. Where correspondence creates a specific response date, track that separately in your planning system and verify it with the authority or adviser.