Built for Australian buyers who need cash clarity
DutyStack is a free consumer toolkit for stamp duty, funds to complete, loan repayments and indicative LMI — plus long-form state learn hubs and worked scenarios. Enter a price once. See how deposits, duty, grants and high-LVR costs stack before you bid.
Last reviewed 2026-08-21
Independent toolkit — not government
DutyStack is an independent product operated by Harbour Lending (Australia). It is not a government website, not affiliated with any state revenue office, and not a substitute for a conveyancer, licensed broker, or credit licensee. Stamp duty rates, concessions, grants and scheme rules change — always verify figures with the official source before you exchange or settle.
Last reviewed 2026-08-21 · Harbour Lending editorial
What we are
A calculation and education site for mainstream Australian residential purchases across all eight states and territories. We publish state buyer hubs, national guides, and worked scenarios so you can see the decision — not just a single number on a thin SEO page.
The calculator is the tool. The learn hubs are the briefing desk. Both stay free for home buyers without creating an account. Returning visitors come back because the state rules, cash worksheet, and engine-backed scenarios are organised the way a deal desk thinks — purpose first, then concessions, then settlement cash.
Editorial standards
State hubs and guides are written as buyer briefings, not keyword templates. When legislation or scheme caps change, we update the modelled paths in @dutystack/core and refresh the “last updated” dates on affected pages. We cite official revenue-office and Housing Australia destinations so you can verify before exchange. We do not invent ABN numbers, fake testimonials, or government affiliation.
If you find an error in a guide or learn hub, email hello@dutystack.com.au with the page URL and the correction. Content corrections are a first-class contact reason — see Contact.
What we are not
We are not a lender, not a broker lead marketplace on the free consumer site, and not a substitute for a conveyancer or credit licensee. Figures are estimates — not a Revenue Office assessment and not credit advice under the NCCP. Unusual structures (trusts, related-party transfers, complex off-the-plan) still need professionals.
Why the calculator is free
Home buyers should be able to check settlement cash without creating an account. Display advertising (Google AdSense) helps cover hosting so the consumer toolkit can stay free. Ads sit beside or below long publisher content and the main calculator — not inside the inputs, and not on thin doorway pages. See Privacy and How it works.
How to use the site
Start with your state learn hub, open a worked scenario when you need a forced comparison, then run the calculator with your real offer. National guides cover cross-state topics like funds to complete, LMI, and auction cash ceilings.
For mortgage brokers
Brokers can embed a white-label version of the toolkit for client-facing sites. That is a separate product from this free consumer calculator. See pricing. The free site does not require signup and does not harvest buyer leads for Harbour Lending.
Who operates DutyStack
DutyStack (dutystack.com.au) is operated by Harbour Lending, Australia. Contact: hello@dutystack.com.au. Editorial review: Harbour Lending editorial, 2026-08-21.
Harbour Lending is not a bank and does not provide regulated credit assistance through this free consumer site. Broker embed accounts are a separate commercial product — see pricing.
Official sources
Use these sites to confirm duty, grants and scheme eligibility for your contract. DutyStack models common residential paths for education; the revenue office assessment wins.
- NSW — Revenue NSW
- VIC — State Revenue Office Victoria
- QLD — Queensland Revenue Office
- WA — Department of Finance (RevenueWA)
- SA — RevenueSA
- TAS — State Revenue Office Tasmania
- ACT — ACT Revenue Office
- NT — Territory Revenue Office
- Home Guarantee Scheme — Housing Australia
Methodology: How it works. Corrections: Contact.