FSI Premium Cost Calculator

Work out fsi premium cost instantly with clear inputs, formula shown and shareable results.

About FSI Premium Cost Calculator

Many jurisdictions allow additional floor space index to be purchased from the planning authority at a premium rate linked to land value. The premium is normally taxable, so the effective cost per square metre is well above the notified rate, and it must be compared against the sale value of the extra area to see whether buying FSI is worthwhile.

Formula

FSI premium

Total = additional area x premium rate x (1 + tax rate)

Worked example

With the default values below, FSI Premium Cost Calculator returns Total premium payable of $28,320,000.00. Change any input above and every figure here is recalculated in your browser.

Inputs used

Additional built-up area purchasedminimum 0.1 m²: 2,000 m²
Premium rateminimum 0 per m²: 12,000 per m²
Tax on the premiumaccepts 0–40 %: 18 %

Results

Total premium payable: $28,320,000.00
Base premium: $24,000,000.00
Tax on the premium: $4,320,000.00
Effective cost per square metre: $14,160.00

Step by step

1Values used
2FSI premium
3Total premium payable= 28,320,000.00
4Base premium= 24,000,000.00
5Tax on the premium= 4,320,000.00
6Effective cost per square metre= 14,160.00

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Preliminary estimate only. Premium FSI rates, eligibility and taxation vary by jurisdiction and must be confirmed with the planning authority.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Preliminary estimate only. Premium FSI rates, eligibility and taxation vary by jurisdiction and must be confirmed with the planning authority.

Frequently Asked Questions

How is the FSI Premium Cost figure worked out?

Total = additional area x premium rate x (1 + tax rate). Many jurisdictions allow additional floor space index to be purchased from the planning authority at a premium rate linked to land value.

When is buying FSI not worth it?

When the premium plus construction cost approaches the achievable sale rate. In weaker markets the premium can exceed the marginal value of the extra area.

What values do I need to enter?

This calculator takes 3 inputs: Additional built-up area purchased, Premium rate, Tax on the premium. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.