PSB rebate backfile: four years to claim

Of the Canadian charities we onboard, the majority have at least two years of unclaimed PSB rebate sitting on the table. Some have four. The rebate is one of the most under-claimed tax recoveries available to charities — and the fix is simply filing.

How the backfile works

The PSB rebate can be claimed by filing Form GST66 and, where applicable, RC7066-SCH for the provincial part of HST. For a charity:

• Non-registrants generally have two claim periods per fiscal year.
• A non-registrant claim must generally be filed within four years of the last day of the claim period.
• A GST/HST registrant claim must generally be filed within four years of the GST/HST return due date for the claim period.
• A claim filed within the four-year window is processed and refunded; one filed after is generally barred.

In practical terms: calculate the window claim-period by claim-period before assuming a year is still open.

Why so many charities miss this

Several reasons we see consistently:

1. No GST/HST registration. Many small charities are not registered for GST/HST (because they’re below the small-supplier threshold) and assume the PSB rebate doesn’t apply to them. It does. Registration is not required.
2. Default chart of accounts. A bookkeeper running a generic chart of accounts often books GST/HST paid as a normal expense rather than tracking it as a recoverable. By year-end, the data needed to file is buried in expense detail.
3. Provincial portion forgotten. Charities in HST provinces (ON, NB, NS, PE, NL) sometimes claim only the federal 50% rebate and miss the provincial portion. Ontario’s 82% provincial rebate is the largest single missed amount we see.
4. Quebec OBNLs file the wrong rebate. Quebec OBNLs need to file both a federal GST PSB rebate and a separate Quebec QST rebate via Revenu Québec. Filing only one leaves the other unclaimed.

How to backfile

For each open claim period:

1. Identify total GST/HST paid during the period from your accounting records.
2. Determine the federal portion and the provincial portion separately.
3. Complete Form GST66 (paper) or file electronically via My Business Account.
4. Apply the correct charity rebate rates by province (50% of the GST or federal part of HST; provincial rates vary).
5. Keep the source documents and calculation schedule with your books and records.

When backfiling pays for itself

Even at modest expense levels, the PSB rebate adds up. A small Ontario charity with $80,000 of annual GST/HST-paid expenses (typical for an organization with $300K-$500K total revenue) recovers approximately:

• Federal portion: $2,000 per year (50% of the federal 5% on $80,000)
• Provincial portion: $5,248 per year (Ontario charity rate of 82% on the 8% provincial portion)
• Approximately $7,250 / year recoverable.

Three years of backfile = ~$21,700. This is real money for a charity at that revenue level.

What to do

If your charity has never claimed the PSB rebate, or claimed only the federal portion, or hasn’t filed in the past few years:

1. Pull GST/HST-paid totals for each claim period still in the four-year window.
2. Use our PSB rebate calculator to estimate the recovery.
3. File the GST66 forms and RC7066-SCH where applicable for each open claim period.
4. Set up monthly tracking going forward so this is no longer a backfile question.

If the numbers look material and the backfile work feels daunting, book a discovery call. Recovery work is a defined-scope engagement we handle frequently.