Stamp Duty Calculator

How we calculate this

The formula

value

the dutiable value, which is normally the purchase price (revenue offices use the higher of the price and the market value)

threshold

the bottom of the duty bracket the value falls into, in your state

base

the fixed duty charged on everything up to that threshold

rate

the marginal rate charged on the part above the threshold

concession

any first-home or owner-occupier relief your state applies, which is often a full exemption up to one value and a taper above it

We then apply:

• Where the scale charges “for every $100, or part of $100” (NSW, Queensland, WA, SA, Tasmania and the ACT), the part above the threshold is rounded up to the next $100 first
• Payable = Duty − concession, and never less than $0

What we assume

• Eight scales, one per state and territory. Duty is a state tax, so there is no national formula. Each scale here is transcribed from the relevant revenue office as at 1 July 2026 (2026-27), with the bracket thresholds, the base amounts and the marginal rates that office publishes.
• Owner-occupiers use a separate scale where the state has one. Victoria has a principal place of residence scale up to $550,000, Queensland has a home concession scale and the ACT has an eligible owner occupier scale. Elsewhere owner-occupiers pay the general rate, and first-home relief is applied on top.
• Thresholds move, usually every year. Several states index their brackets to inflation and all of them can change the scales at budget time. Figures here are a point-in-time transcription, not a live feed from the revenue offices.
• Surcharges and special schemes are not included. Foreign purchaser surcharges, pensioner concessions and new-home relief are outside the model. That includes the ACT Off the Plan Unit Duty Exemption and Newly Unit Titled Duty Exemption, the Victorian temporary off-the-plan concession, South Australia’s seniors downsizing relief for buyers aged 60 or over (homes up to $2.0 million, contracts from 25 March 2026) and the Northern Territory House and Land Package Exemption. Queensland’s home concessions are limited to citizens, permanent residents and specified foreign retirees from 1 August 2026, which the calculator does not test. Where one of these is likely to matter the calculator says so under the result.
• Duty is only part of the cost. Transfer and registration fees, mortgage registration, conveyancing and building inspections are separate, and are not included in this figure.

A worked example

A first-home buyer in New South Wales purchasing an established home for $900,000.

1. Find the bracket the price falls intothe NSW scale charges a fixed base for each bracket plus a marginal rate on everything above its floor, and $900,000 falls in the bracket that starts at $387,000base $11,602, then 4.5% above $387,000
2. Charge the marginal rate on the part above the threshold($900,000 − $387,000) × 4.5%$23,085
3. Add the base for the bracket$11,602 + $23,085$34,687 of duty before any concession
4. Apply the first-home taperthe First Home Buyers Assistance Scheme waives the lot up to $800,000 and tapers to nothing at $1,000,000, so at $900,000 it takes off 50% of the duty on an $800,000 home−$15,094
5. Take the concession off the duty$34,687 − $15,094$19,593 payable

Figures above are rounded for reading, so a line can differ by a dollar from the exact arithmetic. The calculator itself works to full precision.

That purchase attracts an estimated $19,593 of transfer duty, against $34,687 for a buyer with no first-home entitlement. Confirm the exact figure with Revenue NSW before you budget on it.