Read this first: there are two different caps
This page is about the ATO tax rule
Two rules share almost the same name, and confusing them produces a confidently wrong number:
- The ATO defined benefit income cap — a tax rule. It decides how much of your defined benefit pension is added to your assessable income, and how much super income stream tax offset you keep. That is what this calculator does.
- The Centrelink 10% deductible amount cap — a social security rule. It limits the deductible amount for a defined benefit income stream under the Age Pension income test. Different legislation, different agency, different answer. For that, use the Age Pension calculator.
This calculator also does not reproduce the PAYG withholding schedule (Schedule 13, parts A to E). That works out what your fund withholds each fortnight — a payroll calculation for administrators, involving remaining-fortnight counts and two payment summaries in the year you turn 60. It is not the question a retiree asks, and modelling it would multiply the surface area for an audience that does not want the answer.
Who the cap applies to
The cap only has tax consequences if you are:
- 60 years old or over, or
- under 60 and receiving a death benefit income stream from someone who died aged 60 or over.
The ATO puts it plainly: “The defined benefit income cap does not have taxation consequences outside of these circumstances.” If you select the fourth option in the calculator it tells you that, rather than producing a number that means nothing.
Rule 1 — 50% of the excess becomes assessable income
The ATO’s wording:
“50% of your defined benefit income (excluding any amounts from an untaxed element) that exceeds your defined benefit income cap is included in your assessable income.”
Two things are easy to miss. First, the untaxed element is excluded from this test — you can have a very large total income and still owe nothing under this rule. Second, the tax-free component is in it. A tax-free component is normally not assessable at all; above the cap, half the excess becomes assessable regardless. That is the concession being clawed back, and it is the part that surprises people.
Rule 2 — the untaxed element and the 10% offset
An untaxed element is always fully assessable, cap or no cap — that is ordinary treatment, not a consequence of the cap. What the cap changes is your 10% tax offset:
“the 10% offset applicable to the untaxed element-sourced income only applies to the amount of the untaxed element-sourced income up to your defined benefit income cap, and no tax offset applies to the excess.”
The stacking order decides your answer
The ATO is explicit, and this is the sentence that determines the result:
“your taxed element sourced income is counted first (‘stacked’) before your untaxed element sourced income when calculating your entitlement to tax offsets.”
So the tax-free component and taxed element fill the cap first. Whatever room is left is the only part of your untaxed element that earns the offset. If they already exceed the cap, the offset is gone entirely.
⚠ A trap in the ATO’s own withholding wording
Schedule 13, part E words the offset as: “Subtract from the reduced cap the sum of the tax-free component and the taxed element and apply 10% to this amount.”
Read literally that is 10% × headroom — with no reference to how large the untaxed element actually is. Whenever your untaxed element is smaller than the headroom, that overstates the offset, sometimes wildly. A person with a $5,000 untaxed element and no other defined benefit income would compute an offset of $13,125 — more than twice the entire untaxed element.
The offset can never exceed 10% of the untaxed element itself, which is why the formula above takes the lower of the two. The calculator’s test suite pins this exact case, and deliberately fails if the literal reading is ever implemented.
The cap can be reduced part-way through a year
If you turn 60 during the year, start a capped defined benefit income stream during the year, or start a reversionary death benefit income stream during the year, the cap is pro-rated:
The ATO schedule divides by 365 explicitly, including in a leap year. The calculator does the same — substituting 366 would quietly shrink the cap.
Worked against the ATO’s own example: someone turning 60 on 12 September 2026 has 292 days to 30 June 2027. 292 ÷ 365 = 80%, and $131,250 × 80% = $105,000. The calculator reproduces that figure exactly, and the ATO’s second example ($65,805 from 183 days) to the dollar.
Figures used, with sources
| Figure | Value | Source |
|---|---|---|
| Defined benefit income cap — annual | $131,250 | ato.gov.au |
| General transfer balance cap | $2,100,000 | ato.gov.au |
| Defined benefit income cap divisor | 16 | ato.gov.au |
| Share of the excess included in assessable income | 50% | ato.gov.au |
| Super income stream tax offset — untaxed element | 10% | ato.gov.au |
| Super income stream tax offset — taxed element | 15% | ato.gov.au |
| Maximum super income stream tax offset — untaxed element | $13,125 | ato.gov.au |
| Age at which the defined benefit income cap applies | 60 | ato.gov.au |
| Days used to pro-rata a reduced defined benefit income cap | 365 | ato.gov.au |
Every figure is stored with its source and a verification flag, and the build refuses to publish an unverified one — the calculator fails loudly rather than showing an unchecked statutory number.
These figures move on a different date from our other calculators
The Age Pension figures behind our other calculators change on 20 March and 20 September. These change on 1 July, with the financial year, because the defined benefit income cap is the general transfer balance cap divided by 16 and the transfer balance cap indexes on 1 July. This page therefore carries its own effective window rather than inheriting the pension one.
What is not modelled
Stated rather than quietly assumed:
- Your actual tax bill. This shows the extra assessable income and the offset you keep. What that costs you depends on your marginal rate, Medicare levy, and every other item in your return.
- The PAYG withholding schedule (what your fund withholds each fortnight).
- The Centrelink 10% deductible amount cap and the Age Pension income test.
- Excess transfer balance tax, and the interaction where you hold both a capped defined benefit income stream and an account-based pension.
- Multiple income streams with different start dates, or a personal income stream running alongside a reversionary one. The ATO notes that in those cases the pro-rata “may not be correct in all circumstances”.
- The 15% offset on the taxed element, which is shown on your payment summary and is not reduced by this cap.
This is a tax calculation, and tax advice is not what this page is. It shows what the published rule produces from the numbers you enter. For your own position, talk to a registered tax agent or book a conversation with us.
Citing this calculator
Journalists, advisers and researchers are welcome to cite this page. Suggested form:
iAdvice, “Defined Benefit Income Cap Calculator — Methodology and Sources”, https://www.iadvice.net.au/defined-benefit-income-cap-calculator-methodology.htmlEvery figure links to its ATO source. If you find an error, tell us at support@iadvice.net.au and we will correct it and say so.