Stamp duty calculator
/v1/calculators/stamp-duty1¢ per callStamp duty (transfer duty) on a residential purchase in any state or territory, with every step shown: the general-rate duty, each concession or exemption that applies, and the foreign purchaser surcharge.
Who pays it: the buyer, once, at settlement (or within the state's deadline after it). It is usually the biggest up-front cost after the deposit, and it varies widely with the buyer: the same home can cost a first home buyer nothing under a state's exemption cap and a foreign buyer several times the ordinary amount.
What it covers: the general scale; owner-occupier / home concessions;
first home buyer exemptions and concessions for established homes, new homes
and vacant land; off-the-plan, pensioner and income-tested schemes where a
state has them; and the foreign purchaser surcharge. Rates are those in force
on contract_date — each answer names the rates table version and the dates
it applies.
Caveats: an estimate for planning, not a duty assessment. It assumes one
buyer (or all buyers alike) and a home, not commercial or primary-production
land. Mortgage and transfer registration fees are separate and not included.
Each response lists what it assumed in caveats. For first home buyers,
/calculators/first-home sets the duty saving next to the grants.
Authorization
Request
The only values you send. Fields under Responses below are what comes back — you never pass those.
Query parameters
statestringrequiredState or territory: NSW, VIC, QLD, WA, SA, TAS, ACT, NT.
pricenumber0–1000000000requiredPurchase price (or market value, if higher) in dollars.
buyer_typestringoptional`first_home` (first home buyer who will live in it), `owner_occupier` (will live in it, not a first home), `investor`, or `foreign` (a foreign person under state law — surcharge duty applies, no home concessions).
property_typestringoptional`established` (an existing home), `new` (a new home or off-the-plan, never lived in), or `vacant_land` (land to build a home on).
contract_datestring · dateoptionalContract date (YYYY-MM-DD); picks the rates in force on that day. Default: today in Sydney.
off_the_planbooleanoptionalBought off the plan. Changes the answer only where a state has an off-the-plan concession.
regionalbooleanoptionalOutside the capital city (WA: outside Perth and Peel; also the WA grant's northern cap). Ignored where a state draws no such line.
household_incomenumber0–∞optionalGross household income for the past year — used by income-tested schemes (ACT). Omit and we assume you meet the income test.
dependantsinteger0–20optionalDependent children — raises an income-tested scheme's limit (ACT).
pensionerbooleanoptionalHolds an eligible pension or concession card. Changes the answer only where a state has a pensioner concession.
Responses
Successful Response
statestringalways returnedNSW, VIC, QLD, WA, SA, TAS, ACT or NT.
pricenumberalways returnedDutiable value used: the price you passed, or our value estimate on the property route.
price_sourcestringalways returned`input` (you passed it) or `value_estimate` (our estimate for the property).
gnaf_idstringmay be nullThe property, on the property route; null otherwise.
buyer_typestringalways returnedfirst_home, owner_occupier, investor or foreign.
property_typestringalways returnedestablished, new or vacant_land.
foreignbooleanalways returnedWhether the foreign purchaser surcharge was applied.
contract_datestring · datealways returnedDate the rates were picked for.
general_dutynumberalways returnedDuty at the general rate, before any concession.
concessionnumberalways returnedAmount taken off by concessions or exemptions (0 when none apply).
concession_namestringmay be nullThe concession or exemption that applied, if any.
foreign_surchargenumberalways returnedForeign purchaser surcharge duty (0 unless foreign).
total_dutynumberalways returnedWhat you pay: general_duty − concession + foreign_surcharge.
effective_rate_pctnumbermay be nulltotal_duty as a % of price; null when price is 0.
breakdownarray of CalcLinealways returnedEvery step, in order; amounts sum to total_duty.
ratesobjectalways returnedWhich rates table the answer used. Rates change each financial year (or land tax year); the version in force on your date is picked for you.
caveatsarray of stringalways returnedWhat this calculation assumes or leaves out.
About this data
What this is
Stamp duty (transfer duty) on a home purchase in any Australian state or territory, worked out step by step: duty at the general rate, any concession or exemption that applies, and the foreign purchaser surcharge. It covers first home buyers, owner-occupiers, investors and foreign buyers, for established homes, new homes and vacant land.
What people use it for
- Buyers: know the up-front cost before making an offer.
- Mortgage brokers and lenders: add duty to the funds a buyer needs.
- Property and listing sites: show "stamp duty on this price" next to a listing.
- AI assistants: give a correct figure with the working shown.
Tips
Rates follow contract_date, and each answer names the rates version it used. Every state's rates go back to at least 1 July 2025. It is an estimate, not a ruling. For a known property without a price, use /v1/properties/{gnaf_id}/calculators/stamp-duty; for grants as well, use /v1/calculators/first-home.
/v1/calculators/stamp-dutycurl --request GET \
--url 'https://api.microburbs.com.au/v1/calculators/stamp-duty?state=NSW&price=850000' \
--header 'Authorization: Bearer test'{
"data": {
"breakdown": [
{
"amount": 32437,
"detail": "$850,000 on the general rate: $11,602 + 4.5% of the value over $387,000 (per $100 or part).",
"item": "Transfer duty"
},
{
"amount": -22640.25,
"detail": "Concession for a first home (new or established) valued between $800,000 and $1,000,000: the duty on $800,000 ($30,187) shrinks in a straight line to nothing at $1,000,000, so $22,640.25 comes off.",
"item": "First home buyer concession"
}
],
"buyer_type": "first_home",
"caveats": [
"Assumes you are an Australian citizen or permanent resident.",
"You must never have owned residential property in Australia (nor your spouse or partner).",
"For a home, you must move in within 12 months of settlement and live there for 12 months in a row."
],
"concession": 22640.25,
"concession_name": "First home buyer concession",
"contract_date": "2026-11-12",
"effective_rate_pct": 1.153,
"foreign": false,
"foreign_surcharge": 0,
"general_duty": 32437,
"price": 850000,
"price_source": "input",
"property_type": "established",
"rates": {
"effective_from": "2026-07-01",
"version": "NSW-duty-2026-07-01"
},
"state": "NSW",
"total_duty": 9796.75
}
}