Stamp Duty for Limited Companies 2025: Rates, Surcharges and Calculator

Limited company SDLT calculator

Why companies pay higher SDLT

A company is not capable of being a first-time buyer and it does not have a main residence. That means the reliefs and replacement-home logic that can reduce SDLT for individuals usually do not apply.

For residential purchases below the 17% non-natural-person threshold, or where relief from that flat rate applies, a company normally pays the higher residential rates. Those rates are 5 percentage points above the standard residential SDLT bands.

This is why a limited company stamp duty calculator must not use the standard residential calculator result. The company result can be several times higher even on the same purchase price.

The 17% flat rate trap for residential property over £500,000

The highest-risk SDLT rule for company buyers is the flat rate for certain non-natural persons. For relevant residential purchases over £500,000, the rate is now 17% of the whole consideration where no relief applies.

This rule is often described in older articles as the 15% company rate. That is outdated for current transactions: the rate was increased to 17% for transactions with an effective date on or after 31 October 2024.

The flat rate is designed to discourage private enveloping of high-value dwellings in companies. It is not aimed at genuine commercial property businesses, which is why relief can be available where the conditions are met.

How to avoid the 17% rate legally

The 17% rate can be disapplied where a statutory relief applies. Common relief categories include property rental business, property development, property trading, making the property available to the public, employee occupation, financial institution acquisition in the course of lending, farmhouses and qualifying housing co-operatives.

The relief is not automatic simply because the buyer has set up an SPV. The intended and actual use of the property matters. A company that buys a dwelling for a director or shareholder's private use is in a very different position from an SPV buying a portfolio property for commercial letting.

Relief can be withdrawn if the qualifying use stops within the relevant clawback period. The calculator should therefore show both the relief outcome and the unrelieved 17% outcome for purchases above £500,000.

ATED: the annual charge many SPV buyers miss

ATED is the Annual Tax on Enveloped Dwellings. It is an annual tax mainly payable by companies that own UK residential property valued at more than £500,000. It is separate from SDLT and can apply after the purchase has completed.

A genuine property rental business may qualify for ATED relief, but the company may still need to file the correct ATED return or relief declaration. This is why an SDLT calculator should flag ATED risk rather than pretending SDLT is the only tax question.

ATED is especially important for high-value London property, mixed personal/commercial use and situations where a shareholder, director or connected person may occupy the property.

SPV and SPE structures explained

An SPV, or special purpose vehicle, is a limited company created to hold one activity or asset class, commonly buy-to-let property. Some investors and lenders also use the term SPE, special purpose entity.

A clean SPV usually has no trading history outside property ownership and uses property-related SIC codes. That makes lender underwriting easier because the mortgage risk is isolated from unrelated business activity.

The SPV does not make SDLT disappear. Its value is mainly in financing, ring-fencing, reinvestment of profits, portfolio administration and sometimes inheritance or succession planning. The SDLT treatment must still be modelled purchase by purchase.

Worked example: £350,000 individual vs limited company

An individual buying a £350,000 home as their only residential property pays standard SDLT of £7,500: 0% on £125,000, 2% on £125,000 and 5% on £100,000.

A limited company buying the same £350,000 residential property normally pays higher rates of £25,000: 5% on £125,000, 7% on £125,000 and 10% on £100,000.

The company SDLT cost is therefore £17,500 higher than the standard individual cost. That SDLT difference should be weighed against corporation tax, mortgage interest treatment, future profit extraction and the investor's long-term strategy.

Worked example: £600,000 and the 17% trigger

At £600,000, a standard individual residential purchase costs £20,000 SDLT. A company paying normal higher rates costs £50,000. If the 17% non-natural-person rate applies, SDLT is £102,000.

The company higher-rate result is already £30,000 above the standard individual result. The unrelieved 17% result is £82,000 above the individual result and £52,000 above the company higher-rate result.

This is why the calculator should ask about qualifying commercial use and flag professional advice before exchange, not after completion.

When buying through a company can still make sense

Buying through a company can make sense for portfolio landlords who intend to retain profits in the business, investors planning multiple acquisitions, families considering succession planning, and landlords whose personal tax rate makes personal ownership inefficient.

Company ownership can also be appropriate for professional property development, trading, build-to-rent and commercial letting structures. In those cases the company is not merely a wrapper around a private dwelling; it is the operating vehicle for a commercial property activity.

The decision should be modelled over time. Upfront SDLT is only one part of the calculation. Mortgage pricing, tax on profits, extraction of dividends, capital gains, refinancing, ATED, bookkeeping and exit strategy all matter.

Calculator implementation notes

The limited company calculator should first calculate the normal company higher-rate SDLT. It should then test whether the price exceeds £500,000 and whether the buyer is a company or other non-natural person. If yes, it should show a 17% flat-rate risk result unless the user indicates a qualifying relief category.

The tool should not promise that relief applies. It should say: 'Potential relief category selected — confirm conditions with your solicitor or tax adviser.' For non-UK resident companies, it should separately flag the 2% surcharge.