Stamp Duty Calculator

Calculate transfer tax on a property purchase using tiered bands you supply.

Please note: Estimates only, not investment or legal advice. Property markets, taxes, fees and lending rules vary by location and change over time. Verify figures with a qualified professional before committing.

What the Stamp Duty Calculator does

Stamp duty or transfer tax is charged when property changes hands. Most systems use tiered bands where each rate applies only to the portion of the price within that band, though some jurisdictions use a flat rate or slab system where one rate applies to the entire price.

Formula

Tiered: Duty = Σ (Price within each band × That band's rate)
Flat: Duty = Price × Rate
Surcharge = Price × Surcharge rate, added to the base duty

Inputs explained

Input	Unit	Required	Notes
Property price	selected currency	Yes	Accepts more than 0.
Rate structure	one of 2 options	Yes	—
Band 1 threshold	selected currency	In some modes	Price up to here is taxed at rate 1. Accepts 0 or more. Shown Rate structure is Tiered bands (each rate applies to its slice).
Rate 1	%	In some modes	Shown Rate structure is Tiered bands (each rate applies to its slice).
Band 2 threshold	selected currency	In some modes	Accepts 0 or more. Shown Rate structure is Tiered bands (each rate applies to its slice).
Rate 2	%	In some modes	Shown Rate structure is Tiered bands (each rate applies to its slice).
Band 3 threshold	selected currency	In some modes	Accepts 0 or more. Shown Rate structure is Tiered bands (each rate applies to its slice).
Rate 3	%	In some modes	Shown Rate structure is Tiered bands (each rate applies to its slice).
Rate above band 3	%	In some modes	Shown Rate structure is Tiered bands (each rate applies to its slice).
Flat rate	%	In some modes	Shown Rate structure is Flat percentage.
Surcharge	%	Optional	Additional property or non-resident surcharge, applied to the whole price.
Currency	one of 10 options	Optional	—

How to use it

Choose Rate structure and Currency.
Enter Property price.
Fill in the remaining inputs the form shows for your choice.
Optionally add Surcharge.
Select Calculate.

Worked example

A £650,000 property with bands at 250,000 (0%), 925,000 (5%), and a 3% additional-property surcharge.

Price: 650000
Band 1: 250000
Rate 1: 0
Rate 2: 5
Surcharge: 3

First £250,000 at 0%, next £400,000 at 5% = £20,000, plus £19,500 surcharge = £39,500 total.

Reading the result

The "effective rate" blends all bands into one overall percentage — do not confuse it with the top marginal band rate you entered, which is always higher, since earlier bands are taxed at a lower rate.
The "duty at different prices" table shows how the effective rate creeps up with price even though the underlying tax is still banded, useful for judging how sensitive the total is to a slightly higher offer.

Assumptions and limitations

This is a generic band/flat calculator with no built-in jurisdiction data — accuracy depends entirely on the bands, rates and surcharge you enter correctly reflecting the rules where you are buying.
Reliefs such as first-time-buyer discounts or exemptions are not modelled at all unless manually reflected by adjusting a band or rate.

Common mistakes

Entering a jurisdiction's top marginal rate as a flat percentage in "flat mode" when that jurisdiction actually uses tiered bands — this substantially overstates the duty versus the real banded system.
Forgetting the surcharge applies to the whole price, not just the amount above a threshold — a small surcharge percentage on a large purchase can add more to the bill than an entire tax band.

Frequently asked questions

Is stamp duty charged on the whole price or in bands?

Most modern systems use bands, so only the portion within each band is taxed at that rate. Older slab systems charged one rate on the entire price, creating sharp cliffs at thresholds.

Can stamp duty be added to the mortgage?

Usually not — most lenders require it in cash alongside the deposit. Budget for it separately.