Worked example: $120,000 salary, $10,000 sacrificed
Without sacrificing, take-home is $91,080. Sacrifice $10,000 and take-home falls to $84,280 — you gave up $6,800. But $8,500 (the $10,000 minus 15% contributions tax) lands in your super, on top of your employer's $14,400 SG. You traded $6,800 of spending money for $8,500 of retirement money. The $1,700 edge is what's left of the $3,200 income-tax-and-Medicare saving after the 15% contributions tax takes its cut.
Frequently asked questions
How does salary sacrifice save tax?
Money sacrificed into super is taxed at 15% inside the fund instead of your marginal rate (30%, 37% or 45% for most full-time workers) — and it also escapes the 2% Medicare levy. The gap between the two rates is your saving.
What is the concessional cap for 2026–27?
$32,500 a year — and it includes your employer's 12% SG contributions, not just your sacrifice. Many sites still quote the old $30,000 cap. Go over and the excess is added back to your taxable income.
Can I use unused cap from earlier years?
If your total super balance was under $500,000 at the previous 30 June, you may be able to use carry-forward unused cap from up to five years ago. That needs your actual fund data — this calculator flags the standard cap only.
What about Division 293 tax?
If your income plus concessional contributions exceeds $250,000, an extra 15% tax applies to some contributions (30% total). It's assessed later by the ATO, not withheld from your pay.
Salary sacrifice or pay down the mortgage?
The sacrifice saving is immediate and certain; the comparison with mortgage interest depends on your rate and marginal band. The calculator shows the exact tax saving so you can weigh it against your loan's interest cost.
Rates checked against official sources on 1 November 2026: ATO contributions caps and ATO salary sacrificing super. See how we calculate (AU) for the full method.