Is there a late filing penalty for Form RC4288?
No. Form RC4288 is a request for relief, not a return, so it carries no filing deadline of its own and no penalty for going in late. What it does carry is a look-back limit: the request can only reach penalties and interest for years inside that window, so delay costs you access to the older years rather than money on the form itself. The charge most people mean when they search this is the late-filing penalty on the return, and that is the charge the request asks the agency to cancel or waive.
How much of a late filing penalty can an RC4288 request cancel?
Whatever has actually been charged on the return. For the 2025 tax year the late-filing penalty is 5% of the balance owing at the filing deadline, plus 1% of that balance for each full month the return is late, to a maximum of 12 months. A higher rate applies where the agency had issued a demand to file and had charged a late-filing penalty in any of the three preceding tax years: 10%, plus 2% per full month, to a maximum of 20 months. The request asks for cancellation or waiver of that amount and of the interest charged on it.
Can Form RC4288 cancel the tax I owe as well?
No. Relief reaches penalties and interest; the tax itself stays payable. That distinction decides whether the form is worth filing at all. If your complaint is that the assessment is wrong, relief is the wrong instrument, because you are disputing the amount rather than asking for it to be forgiven, and that is a separate route with its own deadline. If the tax is right but the penalties and interest grew because of illness, a disaster, a departmental delay or something comparable outside your control, the request is aimed at precisely that part of the balance.
Do penalties keep growing while the CRA reviews my request?
The late-filing penalty does not compound. Once charged on a return it is a fixed amount. Interest behaves differently: it compounds daily on the unpaid balance, so the balance grows for as long as it sits there, review or no review, and nothing about filing Form RC4288 pauses that. Where the money is available, paying the balance down while the request is being considered stops interest running and does not weaken the request. The request still asks for what was charged up to that point to be cancelled or waived.
How far back can a Form RC4288 request go?
Only as far as the look-back limit allows. The request runs against a window measured from the year it is filed, and penalties and interest for years older than that window are out of reach however good the reasons are. Two things follow. A long stretch of unfiled years usually splits into reachable years and unreachable ones, and the reachable years should not be allowed to age out while the file is being assembled. And where an older year cannot be reached, the only remaining lever on it is the principal, because clearing the balance stops interest compounding.
What evidence do I need to send with an RC4288 request?
A chronology, and documents that support it. The request is a documented narrative of dates, evidence, cause and effect rather than a plea for leniency, and the most common reason one fails is that it asserts a circumstance without showing how that circumstance prevented the filing or the payment. So: what happened, when it started, when it ended, what you did during that period, and the records that corroborate each step. Where a departmental delay forms part of the cause, the dated correspondence showing that delay is the evidence for it.
My T3 or T5 shows foreign income — does that go on the T1135 too?
They answer different questions. The slip reports income you received; the T1135 reports property you held. Foreign income earned inside a Canadian mutual fund or ETF is reported on the slip, but the underlying foreign securities belong to the fund, not to you, so they are not your specified foreign property. Foreign shares held directly in your brokerage account are — even though the broker is Canadian and the account statement is in dollars. See the T1135.
Who has to file an FBAR?
A US person whose foreign financial accounts, added together, exceed the reporting threshold at any point in the year — measured on the aggregate high balance, not on year-end value, and not on income. It captures accounts you merely have signature authority over, so business and family accounts are frequently missed. It is filed with FinCEN separately from the tax return, and its penalties are separate too. See FBAR — FinCEN 114.
