RRSP Over-Contribution Costs 1% a Month. The $2,000 Cushion Is Not Spare Room
An RRSP over-contribution is charged 1% a month, and the words doing the work are in subsection 204.1(2.1) of the Income Tax Act: “Where, at the end of any month after December, 1990, an individual has a cumulative excess amount in respect of registered retirement savings plans, the individual shall, in respect of that month, pay a tax under this Part equal to 1% of that cumulative excess amount.” That Part is Part X.1, headed “Tax in Respect of Over-contributions to Deferred Income Plans”. The charge attaches at month-ends. Not per day, and not per month begun, and of the two dates that bound it, only the one you fix the problem on is still yours to choose.
The $2,000 cushion is real. The first $2,000 above your deduction limit sits inside the shelter and carries no tax, which is why the CRA’s own excess contributions page describes the tax as falling on unused contributions “that exceed your RRSP deduction limit by more than $2,000.” What gets done with that fact is the problem: the cushion gets treated as free tax-sheltered room that may as well be used. For a $2,000 that rides permanently above the limit, which is what happens to a contributor who fills their room every year and so never gets to deduct it, the arithmetic at the end of this piece shows it never beats a TFSA, never beats a taxable holding whose gain is deferred to the end, and needs eighteen to twenty-nine years to beat a taxable holding paying fully-taxed interest. The reason is structural rather than arithmetic. A cushion dollar earns no deduction going in and is taxed in full coming out, so the same $2,000 is taxed twice, while in a taxable account that $2,000 of principal is cost base and is never taxed again.
A $3,000 excess costs $30.00 a month-end and a $14,190 excess costs $141.90
Start with a small excess. An amount of $3,000 above both the limit and the cushion costs $30.00 at each month-end. Paid in February, that is $330.00 across the 11 month-ends from February 28 to December 31, or $30.00 if it is caught and withdrawn during March. Withdrawn without the form discussed below, $300.00 is held back at the 10% band.
A larger excess shows the same mechanics with more at stake. Take a contributor whose 2026 deduction limit is the full dollar limit of $33,810, a limit that current-year accrual alone reaches on 2025 earned income of $187,833.33 at the 18% rate, though room carried forward from earlier years reaches it on much less. They pay $50,000 into an RRSP in February 2026. The cumulative excess is $50,000 less the $33,810 limit less the $2,000 cushion, or $14,190.00, and the tax is $141.90 at every month-end the excess survives.
| Excess withdrawn during | Month-ends the excess stands at | Part X.1 tax |
|---|---|---|
| February (same month) | 0 | $0.00 |
| March | 1 | $141.90 |
| June | 4 | $567.60 |
| September | 7 | $993.30 |
| December | 10 | $1,419.00 |
| not withdrawn in 2026 | 11 | $1,560.90 |
Our arithmetic on Income Tax Act s.204.1(2.1) and s.204.2(1.1), using the 2026 RRSP dollar limit of $33,810 published by the CRA.
Caught during March, the tax is $141.90, because only the February 28 month-end has passed. Left alone, the excess runs through 11 month-ends and the tax is $1,560.90. The difference, $1,419.00, is the price of catching it in December rather than in March. Fixing it fast does not make the paperwork go away: the T1-OVP return is still required and still due March 31, 2027 whether the excess stood at one month-end or at eleven.
That schedule assumes the months can be proved, and the CRA’s own page warns that the paperwork usually does not prove them. It asks for documents that “identify the exact months of all RRSP, PRPP, and SPP contributions and RRSP, PRPP, SPP or RRIF withdrawals”, then adds: “Please note RRSP receipts, T4RSP and T4RIF slips do not contain this information.” Where the documents do not show them, “the CRA may assess the T1-OVP return based on their records”, which means first-60-day contributions placed in January, the rest of the year’s contributions in March, and withdrawals in December. Both defaults run against the taxpayer, pulling contributions earlier and pushing withdrawals later. On the example’s own facts the February contribution becomes a January one and the March withdrawal becomes a December one, so the excess is assessed as standing at 11 month-ends instead of one, $1,560.90 rather than $141.90. Keeping your own record of the dates is worth $1,419.00 here.
The excess is what is left after the whole shelter is counted
Section 204.2(1.1) defines the cumulative excess amount as the amount by which your undeducted RRSP premiums exceed A + B + R + C + D + E. Undeducted premiums are defined separately, at s.204.2(1.2), as H + I – J. H is last year’s undeducted balance, reduced by what was deducted in or before that year, which makes it the letter that carries an unresolved excess forward. I picks up premiums paid in the year and J nets off withdrawals that were included in income.
Element I holds two traps before the shelter is even reached.
The first is spousal. I counts a premium paid under a plan “under which the individual or the individual’s spouse or common-law partner was the annuitant … at the time the premium was paid.” Money put into a spousal RRSP is the contributor’s premium, consumes the contributor’s room, and lands in the contributor’s own undeducted premiums. It does not draw on the spouse’s limit.
The second is the first 60 days of the year, which is where RRSP season puts most contributions. I excludes “an amount paid to the plan in the first 60 days of the year and deducted in computing the individual’s income for the immediately preceding taxation year.” So a February cheque deducted on last year’s return falls out of this year’s element I, having already been accounted for in the preceding year’s computation. A February cheque you intend to deduct against the current year does not. Which year you claim it in decides which year’s limit it is tested against, and that choice is made months after the money moves.
The six letters of the formula are the shelter. A is your unused RRSP deduction room at the end of the preceding taxation year, and if you do not know how yours is built our RRSP rules guide sets out the accrual. R is the year’s total pension adjustment reversal and E is a transitional amount for anyone who turned 18 before 1995.
Two of the letters are rarely explained and both change the answer.
C is the $2,000, and it is $2,000 only “where the individual attained 18 years of age in a preceding taxation year, and in any other case, nil.” In the calendar year a person turns 18 there is no cushion at all. A 17-year-old who earns $10,000 has $1,800 of room in the following year, the year they turn 18, and on our arithmetic a $5,000 contribution that year leaves a $3,200 cumulative excess: $32.00 at each month-end, $384.00 over twelve of them. The same facts one year later, with C at $2,000, leave $1,200.
C is not a lifetime quota either. It is a $2,000 element in every year’s computation of the cumulative excess, so clearing an excess does not use the cushion up. The same $2,000 of tolerance is there the next year, and the year after.
B is the current year’s accrual, and the precise wording matters for everything below: the amount by which the lesser of the year’s RRSP dollar limit and 18% of earned income for the preceding taxation year exceeds the prior year’s pension adjustment and any prescribed amounts. New room is therefore inside the shelter from January, before it has been reported or claimed, which is the mechanism behind the self-cure further down. It is also the mechanism that fails for anyone whose earned income stops.
The two dollar figures in B and C move in opposite directions over time. The CRA’s RRSP dollar limit table runs $31,560 for 2024, $32,490 for 2025, $33,810 for 2026 and $35,390 for 2027. The $2,000 in element C does not move at all: the indexing machinery in section 117.1 adjusts “each specified amount in relation to tax payable under this Part or Part I.2”, and its list of specified amounts runs exhaustively from (a) to (t) without reaching Part X.1, where the over-contribution tax lives. The cushion is a flat figure in the Act, shrinking against the limit it sits above every year that limit rises.
Element D is the group plan amount, defined at s.204.2(1.3), and it gives relief for premiums remitted on your behalf by whoever pays you. It is not confined to employees: s.204.2(1.31)(b) reaches a premium the individual is entitled to “for services rendered by the individual (whether or not as an employee)”. Three features of it are worth knowing before relying on it. The relief is the least of three amounts rather than a single cap: F, then F minus (G minus K), then the cumulative excess computed as if D were nil, and the following year’s RRSP dollar limit caps only F. The arrangement must qualify, and s.204.2(1.32) requires that premiums be remitted “on behalf of two or more individuals”, while excluding any arrangement where it is reasonable to consider that one of its main purposes is reducing tax under Part X.1. And s.204.2(1.31) excludes the part of a premium that, “by making (or failing to make) an election or exercising (or failing to exercise) any other right under the plan” after joining and within the preceding 12 months, “the individual could have prevented” without it having to be remitted elsewhere. A contribution you chose, or chose not to switch off, can fall outside the relief on that wording.
Where the governing number comes from
Everything above runs off one figure, the RRSP deduction limit the CRA assesses, which in the formula is elements A and B taken together. The agency’s plain-language definition of an excess is worth reading before doing any arithmetic against it: you have excess contributions where “your unused RRSP, PRPP, and SPP contributions from prior years and your current calendar year contributions are more than your RRSP deduction limit … plus $2,000.”
The number is published to you rather than left to be worked out. The CRA’s page on where to find your RRSP deduction limit points first to “The RRSP Deduction Limit Statement, on your latest notice of assessment or notice of reassessment”. Where the limit has changed, or where that statement was not included on the notice, the agency may send Form T1028, “Your RRSP Information for 2025”. The limit is also available by signing in to a CRA account online, and “You can also get your RRSP deduction limit by using our automated phone services.” If you would rather work it out than wait for the notice, our RRSP contribution room calculator builds the figure from your own earned income, pension adjustment and carried-forward room.
Two things follow from the definition. Unused contributions from prior years count, so an excess can be standing in a year you contributed nothing at all. And one document does double duty: the same notice of assessment that carries the governing figure is what s.146(8.2)(c)(ii) dates the withdrawal window from, the year “a notice of assessment for the taxation year … was sent to the taxpayer”. Detection and deadline are anchored to the same piece of paper.
The excess can cure itself, and for some contributors it never does
For the contributor in that example the excess then cures itself. At the January 31, 2027 month-end, holding 2026 earned income at the 2025 level, element B is 18% of $187,833.33, or $33,810.00, which is the lesser of that and the 2027 dollar limit. Undeducted premiums are $16,190.00, being the $50,000 paid less the $33,810 deducted on the 2026 return, and they sit against A of $0.00, B of $33,810.00 and C of $2,000.00, a shelter of $35,810.00. The cumulative excess is nil and the tax stops without anyone doing anything.
An excess standing today, October 6, 2026, has three month-ends left in the year: October 31, November 30 and December 31. The T1-OVP for 2026 falls due on March 31, 2027, and if earned income continues, the January accrual may end the problem before that return is even filed.
The self-cure depends entirely on element B, and B is 18% of the preceding year’s earned income. A year with no earned income generates no new accrual, so for someone who retires, is laid off, or steps away from work after over-contributing, nothing arrives in January to absorb the excess. Element H simply carries the undeducted balance into the next year, and the tax keeps being charged.
On the same $14,190.00, that is $1,702.80 over 12 month-ends, $3,405.60 over 24 and $5,108.40 over 36. The excess does not decay on its own at any point. Only a withdrawal, or new room from somewhere, ends it. A reader whose earning years have finished should treat the waiting strategy below as unavailable.
The tax is several times what a year of shelter can save
An excess of any size costs 12% of itself a year. The most that sheltering a dollar of return can be worth over the same year is the marginal rate multiplied by the return, and that is a ceiling rather than an estimate, because it credits the shelter with the full rate on every dollar of return in the year it arises: 1.20%, 1.60% and 2.00% at 30%, 40% and 50% rates on a 4% return; 1.80%, 2.40% and 3.00% on a 6% return; 2.40%, 3.20% and 4.00% on an 8% return.
The tax is 10.0 times the benefit in the worst of those nine cells and 3.0 times it in the best. Across every return in that table an excess loses money in every month it stands, and the ceiling only climbs to meet the 12% tax at a 24% return and a 50% rate. The only real question is how quickly it ends.
Withdrawing it, and what the two forms do
The starting point is unforgiving. Under section 146(8) the whole withdrawal is included in income as a benefit out of an RRSP, and nothing in that subsection turns on whether the contribution was ever deducted. Taking back your own over-contribution is a taxable event unless something offsets it, and s.146(8.2) is that something.
Its timing limb allows the deduction where the payment is received in the year the premiums were paid, the year a notice of assessment for that year was sent, or the year immediately following either of those. Its anti-avoidance limb is a two-part conjunctive test, and both parts must be reasonable to consider before the deduction is denied: that the taxpayer did not reasonably expect the full premiums to be deductible in the year paid or the immediately preceding year, and that the premiums were paid with the intent of receiving a payment that would be deductible under the subsection. That is the statute. The CRA’s administrative position is blunter, and anyone contemplating a deliberate over-contribution needs both halves: on its page for withdrawing the unused contributions the agency states that deliberate over-contributions made in order to withdraw them disqualify the offsetting deduction, and it phrases the condition as requiring that you either reasonably expected to deduct the contributions in the contribution year or the one before, or did not intend to withdraw them to claim an offsetting deduction.
Form T3012A releases the money with no tax withheld, and the CRA lists three conditions that must all be met: “You have not deducted, for any year, the unused contributions”; “You have not designated the withdrawal of the unused RRSP, PRPP or SPP contributions as a qualifying withdrawal to have your PSPA certified”; and “No part of the withdrawn contributions was a lump-sum amount from an RPP, an SPP, a PRPP”.
Without that form, tax comes off at source on the CRA’s withdrawal rates, 10% on amounts up to $5,000, 20% on amounts exceeding $5,000 up to and including $15,000, and 30% on amounts over $15,000 for residents outside Quebec, with 5%, 10% and 15% federally plus provincial withholding in Quebec. Form T746 then computes the deductible amount on the return. The $14,190.00 in the example falls in the middle band, so $2,838.00 is held back and credited against the year’s tax when the return is filed.
Waiting it out against withdrawing it, in one place
These two courses get discussed in different units, so here they are in the same ones, on the $14,190.00 excess.
| Course | What it costs | What it takes |
|---|---|---|
| Leave it and wait for new room | $141.90 at each month-end it survives, $1,560.90 across the 11 month-ends in the example | Earned income in the prior year, so element B delivers new room; the T1-OVP by March 31, 2027 |
| Withdraw using a T3012A | the month-end tax already charged, nothing withheld | all three CRA conditions met; the T1-OVP for the month-ends charged |
| Withdraw without a T3012A | the month-end tax already charged, plus $2,838.00 withheld at the 20% band | a T746 with the return to claim the offsetting deduction; the T1-OVP |
Our arithmetic on the $14,190.00 excess, using the CRA withholding bands. The $2,838.00 is a float rather than a cost: it is credited against the year’s tax on the return.
The money left in the plan is not wasted while it waits. It stays invested and stays available as a deduction once room exists to claim it, and our piece on carrying an RRSP deduction forward covers how that claim works in a later year. Waiting buys time at 1% of the excess each month-end, and it is frequently the right answer, but only for a contributor whose element B will actually deliver.
The T1-OVP is due 90 days after year end, and the waiver is discretionary
The CRA requires the T1-OVP return and the tax “no later than 90 days after the end of the year in which you had the excess contributions.” For a 2026 excess that is March 31, 2027, on our count of 31 days in January, 28 in February and 31 in March. There are two versions of the return and element D decides which one you file: the agency directs an ordinary excess to the simplified T1-OVP-S and reserves the full T1-OVP for an excess involving mandatory contributions to a group RRSP or PRPP.
Filing late compounds the problem twice. The penalty is 5% of the balance owing plus 1% of the balance for each month the return is late, to a maximum of 12 months. On the $1,560.90 from the example, our arithmetic puts one month late at 6%, or $93.65; six months at 11%, or $171.70; and the full twelve at 17%, or $265.35. Interest is then compounded daily on the unpaid tax and on the unpaid penalty, running from the 91st day of the following year.
A waiver can remove the tax, though not as a way of leaving the excess where it is. Section 204.1(4) applies where the individual “establishes to the satisfaction of the Minister” both that the excess “arose as a consequence of reasonable error” and that “reasonable steps are being taken to eliminate the excess.” The burden is on the taxpayer, the two limbs are joined by “and”, so a genuine mistake that is left standing does not qualify, and the operative verb is “may waive”. That is a discretion, not an entitlement, and the request is made on Form RC2503. Anyone counting on a waiver should assume the tax is payable and be pleased if it turns out not to be.
A cushion dollar that is never deducted is a poor shelter
Now the claim the cushion exists to tempt: park $2,000 above your limit, pay no Part X.1 tax on it, and let it compound tax-free.
One condition governs everything in this section. It applies to a $2,000 that is never deducted, which describes a contributor who fills their room every year so the cushion rides permanently above the limit. If room ever opens and the $2,000 is deducted, it is an ordinary RRSP contribution and none of what follows applies to it.
A reader who has got this far will spot an objection, and it is the right one: an undeducted premium can be withdrawn with the s.146(8.2) deduction, which looks like a route by which a cushion dollar would escape being taxed twice. The timing limb quoted above is what closes it. That deduction is confined to a withdrawal received in the year the premiums were paid, the year a notice of assessment for that year was sent, or the year immediately following either. A cushion dollar deliberately held for a decade is years outside the window, so the only route out is an ordinary withdrawal taxed in full under s.146(8).
Which makes the cushion after-tax money that gets taxed again. It earns no deduction going in, because by definition it exceeds the limit you are able to deduct, and the whole withdrawal is income coming out. Writing G for (1 + r) to the power of n and m for the marginal rate, the cushion ends with 2000 x G x (1 – m).
A TFSA ends with 2000 x G. The cushion loses for any rate above zero, at every horizon and every return, and there is no case to argue.
A taxable account splits into two cases, and the cushion loses one of them outright. Consider first the case worst for the cushion, a holding whose whole return is a capital gain deferred to the end of the horizon, where section 38(a) includes “½ of the taxpayer’s capital gain for the year from the disposition of the property” in income. That gain is realised at the same moment and at the same rate as the RRSP withdrawal it is being compared with, so the taxable account ends with 2000 x G less 0.5 x m x (2000 x G – 2000), and the difference comes out as:
-0.5 x m x 2000 x (G + 1)
That expression is negative for every rate above zero and every horizon. There is no break-even and no condition to hunt for. The reason is structural rather than arithmetic, and it is the whole point: in the taxable account the original $2,000 is adjusted cost base and is never taxed again, while in the cushion that same $2,000 is taxed in full a second time on the way out. A longer horizon makes the gap larger, not smaller.
| Marginal rate | Behind after 10 years | after 30 years | after 50 years |
|---|---|---|---|
| 30% | $837.25 | $2,023.05 | $5,826.05 |
| 40% | $1,116.34 | $2,697.40 | $7,768.06 |
| 50% | $1,395.42 | $3,371.75 | $9,710.08 |
Our arithmetic on the difference -0.5 x m x 2000 x (G + 1), at a 6% return, against a taxable account holding a capital gain deferred to the end of the horizon and taxed on the ½ inclusion in Income Tax Act s.38(a). One rate applies to both the withdrawal and the gain, since both happen at the end of the same horizon.
The other case runs the other way and belongs here plainly: a taxable holding paying fully-taxed interest every year is the cushion’s best comparator, because annual taxation of interest is the one drag a registered plan genuinely removes. There the cushion does eventually win, and the table below is how long it takes.
| Annual return | Break-even at a 30% rate | at 40% | at 50% |
|---|---|---|---|
| 5% | 24.8 years | 26.6 years | 28.8 years |
| 6% | 20.8 years | 22.3 years | 24.1 years |
| 7% | 18.0 years | 19.3 years | 20.8 years |
Our arithmetic, against a taxable account holding interest taxed every year as earned, on a $2,000 that is never deducted. Below the break-even the cushion is behind.
Eighteen to twenty-nine years of commitment, on the most favourable comparator, to beat an ordinary taxable account. Against a TFSA and against a deferred gain it does not get there at all. So the cushion is not a shelter worth filling on purpose, and a reader who was about to fill it has $2,000 to place somewhere: the account order is the real question, and our guide to choosing between a TFSA, an RRSP and an FHSA works through where it should go.
What the cushion is actually for
Element C is tolerance, not capacity. It absorbs the employer contribution nobody modelled, the pension adjustment that landed differently than expected, the month that got miscounted, the few hundred dollars of room that was already spoken for. In every one of those cases it does its job and it does it for free: no tax, no T1-OVP, no waiver request, no withdrawal, no withholding to wait out.
The error it forgives is small and accidental, and it is worth the most to the contributor who never touches it deliberately. Used on purpose, as a $2,000 that is never deducted, it is the mistake.
Disclaimer: The content on bestcanadianstocks.ca is for informational and entertainment purposes only and does not constitute financial advice. Past performance is not indicative of future results. Always consult a qualified financial advisor before making investment decisions. Statutory references are to the Income Tax Act as consolidated at the Justice Laws website, a text stating it is current to September 21, 2026 and last amended on June 18, 2026. The RRSP dollar limits, the withholding bands, the T1-OVP deadline, the late-filing penalty and the interest rule are the Canada Revenue Agency’s published figures, retrieved October 5, 2026, with the default month-assignment rule and the T1-OVP-S split retrieved October 6, 2026. The month-end penalty schedules, the comparison of the $2,000 cushion against a TFSA and against a taxable account, and the break-even horizons are our own arithmetic on those figures, at the returns and marginal rates named beside each. The cushion comparison holds for a $2,000 that is never deducted.
