The sacrificed amount is redirected before income tax

An effective salary sacrifice arrangement replaces salary that would otherwise be paid with an employer contribution to super. The employee’s assessable salary is generally reduced by the sacrificed amount, while the fund generally pays tax on concessional contributions. That can make the after-tax cost to the employee lower than the gross amount entering super.

The calculator asks for the marginal income-tax and other marginal effects applying to the dollars sacrificed. It does not infer them from annual salary, because offsets, Medicare levy thresholds, HELP repayment income, family circumstances and other income can make the true movement different. Use an official tax calculation before finalising payroll instructions.

The immediate advantage is not an investment return. The money is preserved in super, is exposed to fees and market performance, and usually cannot be accessed until a condition of release is met. It simply compares two after-tax starting amounts under the entered rates.

Count every concessional contribution against the right cap year

Moneysmart’s current optimiser states that the general concessional contributions cap is $32,500 from 1 July 2026. The cap had been $30,000 from 1 July 2024. The field is editable because a different financial year, carry-forward eligibility or another rule can change the amount relevant to a person.

Concessional contributions generally include employer super guarantee, salary sacrifice and personal contributions claimed as a tax deduction. Amounts across all funds are combined. Contributions count in the financial year the fund receives them, which may not be the pay period or quarter in which they were earned.

The calculator adds the proposed sacrifice to one entered total for all other concessional amounts. A positive gap means the scenario sits below the entered cap. A negative gap flags an excess against that entered cap; it does not calculate the ATO assessment, release election, tax offset or any carry-forward amount.

Unused cap amounts from earlier years may be available under carry-forward rules when eligibility conditions are met. Total super balance and the relevant prior years matter. Check ATO online services and current rules rather than raising the cap field merely to make the warning disappear.

Make the agreement prospectively and in writing

ATO guidance says the arrangement should be entered before the work is performed. An attempted sacrifice of salary already earned may be ineffective. A written agreement should record the amount or method, start date, destination fund, change process and what happens if payroll cannot make a contribution.

From 1 January 2020, sacrificed ordinary time earnings remain in the ordinary-time-earnings base used for super guarantee, and salary sacrifice contributions cannot be used to reduce the employer’s minimum SG obligation. Ask payroll to show compulsory employer contributions separately from voluntary sacrificed amounts.

Payday Super reforms apply from 1 July 2026, but contribution timing and payroll implementation still need to be checked with the employer and fund. Confirm when amounts will be received, especially near 30 June. A payslip deduction does not itself prove the contribution is in the fund for that cap year.

Review the agreement when salary, hours, bonus arrangements, leave without pay or employment changes. If sacrifice would reduce cash salary below an employer, award or practical minimum, payroll may reject or adjust it. The calculator only enforces that sacrifice cannot exceed entered cash salary.

Marginal rates need more care than a tax bracket lookup

The income-tax rate field should reflect the rate on the next dollars removed from taxable salary. The other marginal field can include an ordinary Medicare levy effect where appropriate, but a flat 2% assumption may be wrong near thresholds or for an exemption or reduction.

Salary-sacrificed super is reportable. Although it is not included in taxable income in the same way as cash salary, reportable super contributions are added back for several income tests and obligations. The ATO lists impacts that can include HELP repayment income, Medicare levy surcharge tests, child support and some concessions or payments.

Division 293 can impose additional tax for high-income individuals. Excess concessional contributions also have their own treatment. Set the contributions-tax rate higher only as a rough sensitivity test; do not assume one percentage captures an actual assessment.

Balance tax efficiency against accessible cash

Extra super can improve long-term retirement resources, but the sacrificed cash is generally preserved. Keep enough accessible savings for rent or mortgage, bills, emergencies, insurance excesses and near-term goals. Borrowing at a high rate because too much cash was locked away can overwhelm the initial tax benefit.

Compare salary sacrifice with a personal deductible contribution where eligible. Both can be concessional, but timing, paperwork and cash-flow control differ. A personal deduction requires a valid notice of intent and fund acknowledgement before the relevant deadline and events. Do not claim a deduction merely because a payment was made.

Low- and middle-income outcomes can include LISTO or government co-contribution considerations, while after-tax contributions use a different cap. Couples may benefit from contribution splitting or spouse contribution strategies subject to rules. This page intentionally isolates the before-tax sacrifice decision.

Model investment fees, insurance premiums in super, asset allocation and time horizon. The net contribution shown is a starting balance, not a retirement guarantee. Revisit the amount after pay rises and at least annually when caps and tax settings are known.

Reconcile the first payslip and fund receipt

Divide the annual amount by the selected pay frequency to obtain the intended deduction. A monthly frequency assumes 12 pays, fortnightly 26 and weekly 52. If a year has an unusual pay count or the arrangement starts part-way through the year, calculate the remaining-pay amount separately.

On the first payslip, check gross cash salary, sacrificed super, PAYG withholding and employer super lines. The take-home movement will not necessarily equal this calculator because payroll withholding uses official schedules and may include HELP, allowances, deductions or rounding.

Then confirm the contribution appears in the fund with the correct contribution type and date. Keep the agreement, payslips and fund transactions. If something is missing, contact payroll promptly; contribution caps are based on fund receipt and cannot always be repaired by relabelling after year end.