South Australia property · Land tax

The Land Tax Shock: Why SA Site Values Jumped 30% and How to Object

The Valuer-General's own average rise was 16.2%. If your site value jumped far more, and your land tax bill doubled, here's why it happened and how to object within 60 days.

By Mark Trimboli · 6 November 2026

Opinion and general information only, not financial, tax or legal advice. Scott and Charlene are fictional; their figures are illustrative.

The envelope that didn't add up

Scott and Charlene's Modbury home is exempt from land tax. But years ago, before the kids, they started buying modest investment properties in Adelaide's northern suburbs. That small portfolio is their retirement plan, so they won't have to lean on the Age Pension.

In November, the 2026-27 land tax notice arrived. Charlene read it twice.

Their properties hadn't changed. No renovations, no new zoning, nothing. Yet the land under them was suddenly valued about 30% higher, and their land tax had more than doubled.

Then Charlene found the Valuer-General's own fact sheet. The average statewide increase in residential site values was 16.20% (Office of the Valuer-General, Understanding 2026-2027 Property Values).

"So the average went up 16%," she said, "and ours went up 30%. Why?"

The short answer

Here's why it happened, how to fight it, and what should change.

1. Why a 30% rise doubled the bill

Land tax is charged on site value: the value of the land only, not the house on it. The Valuer-General sets it as at 1 January each year, based on sales in the previous calendar year. So the 2026-27 bill reflects what happened to prices during 2025.

Land tax works in bands, like income tax. The more land you hold in total, the higher the rate on the top slice. Each year the bands move up, but only by the statewide average change in site values. For 2026-27 that was 12.44% (RevenueSA).

Scott and Charlene's land rose about 30%. The bands rose 12.44%. So more of their land spilled into the higher band:

About $2,390 of their $2,705 increase came from that one band. When your values rise faster than the average, the bands don't keep up, and the bill climbs far faster than the land does.

2. The public data doesn't back a 30% rise

The Valuer-General doesn't value each block one by one. Properties that are similar in location, size and use are grouped into sub-markets, and one index is applied to everyone in the group (Valuer-General fact sheet). That's efficient, but it means your block can be swept up in a rise that doesn't fit it.

Scott and Charlene put their increases next to the government's own numbers:

Every public measure lands around 14% to 16%. Their land came in at roughly double. And none of the suburb-wide numbers account for what makes a particular block less attractive: a freight line out the back, an awkward shape, a busy road out front.

3. How to object, with evidence that works

You can object to your site value online, by email or by post. The rule that matters most: you must lodge within 60 days of receiving your first rates or taxes notice for the year, whether that's from council, SA Water or RevenueSA (Valuer-General). Keep paying your land tax while the objection is assessed.

Here's the approach Scott and Charlene took:

1. Compare your increase to the averages. If the Valuer-General increased your site value by far more than its own 16.20% residential average, say so, quoting the fact sheet. (Compare this year's site value on your notice with last year's.)
2. Use government sales data for the right period. Values are set from 2025 sales, so use suburb median prices from Q4 2024 to Q4 2025 (Metro Median House Sales). Apply that growth to last year's site value to suggest a figure.
3. Find vacant land sales. Site value is land only, so recent sales of empty blocks nearby are strong evidence. Adjust them for size.
4. List what makes your block less valuable. For example:
   • a railway or freight line nearby
   • an irregular or tapering shape
   • frontage to a busy arterial road
   • aircraft noise or airfield overlays
   • a steep or uneven slope
   • a block too small to subdivide
   • above-average crime in the suburb (SA crime statistics)
5. Back it with official reports. A PlanSA parcel report shows zoning and overlays. PropScan pulls together zoning overlays, subdivision potential, slope and nearby infrastructure for any SA address, in one report you can attach.
6. Spot inconsistencies on your own notice. Scott and Charlene found a smaller block valued higher than a larger one nearby. That's worth pointing out.

Two cautions. Be honest about the sales evidence, because the Valuer-General sees every sale, not just the ones you pick. And object to the site value only, the figure your land tax is based on.

Now what: the bands need a rethink

Objecting fixes one valuation. It doesn't fix the system. SA's land tax bands do move each year, but they're tied to the statewide average, and the rates on top haven't changed in years:

Source: RevenueSA, rates and thresholds. Land held in most trusts is taxed from just $25,000.

Scott and Charlene see four problems:

• One-size indexing. Thresholds rose 12.44% this year. Residential site values rose 16.20% on average, and some suburbs much more. Owners in fast-rising areas get pushed into higher bands every year.
• Big jumps, no smoothing. One year's sales set the whole bill, so a hot year can double it. Queensland taxes the lower of the current value or a three-year average, and NSW taxes a three-year average of land values. SA could do the same.
• Growth is taxed, not income. A single investment property can drift into land tax purely because its value rose, even if the rent hasn't.
• Retirement savings are taxed every year. Property held in a self-managed super fund pays land tax at the general rates. The whole point of that asset is to fund retirement without relying on the Age Pension.

There's also a timing trap. Land tax is set by who owns the land at midnight on 30 June. If you're developing a site and the project runs past 30 June, you're liable for the full year ahead. If you sell, any adjustment for the rest of the year has to be agreed at settlement (RevenueSA Guide to Legislation: Land Tax 2026-27).

For Scott and Charlene, the sums have changed, and they've started looking at buying their next property interstate. But they checked first, because land tax is everywhere except the Northern Territory, and SA's tax-free threshold is actually one of the most generous:

Source: CheckRate, Land tax by state 2026, compiled from state revenue offices.

So the problem isn't that SA charges land tax, or that its threshold is low. It's that SA bases the bill on a single year's valuation, while NSW and Queensland both use three-year averaging, and indexes its bands to a statewide average. When one hot year lifts your site values 30%, there's nothing to cushion the hit. That makes long-term planning hard, and it's why investors like Scott and Charlene are weighing up whether to keep building their portfolio here.

Does spreading across states help?

Often, yes. Land tax is charged state by state, and each state only adds up the land you hold within its borders. A portfolio spread across states can sit under several tax-free thresholds at once.

Take three investment properties, each with $400,000 of land:

2026 general rates for individuals; excludes trusts and surcharges.

Notice that keeping all three in SA beats spreading them into a low-threshold state like Victoria. Spreading only pays if you pick states with high thresholds.

And tax shouldn't drive the purchase. Growth, rent and the local market matter more. Owning across states also means different tenancy laws, property managers and costs. Rules can change too: Queensland once planned to count land held in other states, before dropping the idea in 2022.

This is one property investor's opinion, not financial advice. Get advice on your own circumstances before restructuring a portfolio.

So what should you do?

Scott and Charlene lodged their objections, one per property, each backed by government sales data, vacant land sales and a list of what makes the block less valuable. It took a few evenings. If they succeed, their land tax drops by about $2,000 a year.

If your land tax notice made you read it twice:

1. Check your site value increase against the Valuer-General's 16.20% residential average.
2. Check your deadline: 60 days from your first rates or taxes notice this financial year.
3. Gather your evidence, and object online.

And tell your local MP that land tax bands tied to a statewide average, with no smoothing, aren't fit for a market moving this fast.

This article is the opinion of a property investor, shared as general information. It is not financial, tax or legal advice, so speak to a qualified adviser before acting on it. For a strong objection, consider a report from a certified practising valuer.