How to calculate a four-day week salary
A four-day week page should explain the method, not only preload the calculator. If a standard role is five equal days and you move to four, the usual gross starting point is 4/5 of the full-time salary before tax, unless the employer keeps pay or benefits structured differently.
| Full-time salary | Four-day equivalent | Simple method |
|---|---|---|
| $80,000 | $64,000 | $80,000 × 4/5 |
| $100,000 | $80,000 | $100,000 × 4/5 |
| $125,000 | $100,000 | $125,000 × 4/5 |
Then use the calculator to see what happens after resident tax, Medicare, HELP and super are applied.
Why the four-day comparison matters
Cash flow
You need the after-tax answer, not just the new annual salary. A four-day arrangement can look more manageable once you compare the net figures side by side.
Hourly value
Some people accept a lower annual salary because the trade-off in time is worth it. Compare hourly or daily take-home as well as annual net pay.
Super and future trade-offs
A lower earnings base usually means lower employer super. That is worth checking before you treat a four-day arrangement as a pure lifestyle decision.
How to use the calculator properly
- Run the existing full-time salary first.
- Then enter the four-day equivalent salary or hours.
- Compare annual net, monthly net, super and any HELP repayment changes.
- If your employer keeps some benefits constant, adjust the assumptions rather than relying on a clean 80% rule.
When a four-day week is not a simple 80% case
Some employers preserve leave, benefits or part of pay. Some arrangements reduce hours but not expectations, while others are genuine part-time contracts. That is why the page needs both a quick rule of thumb and a flexible calculator.
Source-backed notes
- ATO super guarantee confirms the SG rate is 12% from 1 July 2025.
- ATO ordinary time earnings guidance explains which payments count for super guarantee purposes.
Frequently asked questions
How do I calculate a four-day week salary?
The simple starting point is a pro-rata method. If a full-time role is five equal days, a four-day schedule is usually 4/5 of the annual salary before tax unless the employer keeps some pay or benefits unchanged.
Does a four-day week always mean a 20% pay cut?
Not always. Many arrangements do reduce salary by about 20%, but some employers preserve part of the salary or restructure the role around output rather than a simple day-for-day ratio.
Will super and HELP change too?
They can. Lower annual income can reduce employer super and may also change HELP or Medicare settings depending on the final income level.