Land Value vs Purchase Price: The Number That Actually Sets Your Land Tax

What land value (site or unimproved value) actually means

Land value is the assessed value of the land alone, disregarding the house, the pool, the landscaping and most other improvements sitting on it. Each state and territory's valuation authority produces this figure on a rolling basis, and the label varies by jurisdiction — you will see it called site value, unimproved value or simply land value depending on where the property sits.

The contrast is with capital improved value, which covers land plus buildings and is much closer to what a property trades for. Your purchase price is different again: it is whatever you agreed to pay for the whole package on the day. Three numbers, three purposes — and land tax keys off the first one only.

Where to find a property's land value

• —Council rates notice — statutory valuations, commonly including the land or site value, appear here; for a property you are evaluating, asking the selling agent for a copy of the current rates notice is a routine request.
• —Valuation notices issued by your state's valuation authority (typically the Valuer-General), sent to owners when values are reassessed.
• —Land tax assessment notices from the state revenue office, if the current owner already pays land tax.
• —Vendor disclosure documents supplied with the contract of sale, which commonly include the rates notice.

The ~60% heuristic: houses vs apartments

When the actual land value is not available, Plintha's modelling default for a house is roughly 60% of the purchase price — a working assumption, always flagged [ESTIMATE] in the report with the assumption shown, and always overridable once you have the real figure from a rates notice.

Apartments work differently. A unit owner holds only a fraction of a shared site, spread across every apartment in the building, so the land value attributable to any single unit is far lower relative to its price than for a house. Land tax is generally assessed in brackets on the total taxable land value an owner holds in a state, which is why it tends to bite harder on a house than on a unit bought for the same money — and why applying a house heuristic to an apartment would badly overstate the liability.

Why land value — not price — drives land tax

Stamp duty and land tax are often mentioned in the same breath, but they work off different bases entirely. Stamp duty is a one-off charge on the purchase price — a capital acquisition cost that is not annually deductible and instead gets added to your CGT cost base. Land tax is an annual charge on the assessed land value, and on an investment property it is generally deductible against your rental income. Your principal place of residence, by contrast, is generally exempt from land tax altogether.

The split between land and building matters for depreciation too. Division 43 capital works deductions — 2.5% per year straight-line over 40 years for residential buildings constructed after 15 September 1987 — apply to the building, never the land. A property whose value sits mostly in the land carries a bigger recurring land tax cost and a smaller depreciable base at the same time.

How Plintha models land value and land tax

Plintha computes land tax with exact bracket maths, alongside stamp duty computed exactly for all eight states and territories and verified against each revenue office. Where the land value is unknown, the ~60%-of-price house heuristic steps in, clearly marked [ESTIMATE] so you can see precisely which figures are computed and which rest on an assumption — every number in a Plintha report carries its provenance as computed, [ESTIMATE] or [ASSUMED].

Once you have the real land value from a rates or valuation notice, you can override the estimate and the analysis recalculates on the actual figure. The free tier includes one analysis per month with no card required, so you can test the difference the real number makes on a property you are watching.

Common questions