How Capital Gains Tax Works on BTL Sales
Capital gains tax (CGT) is charged on the profit you make when selling a property — the difference between what you paid for it and what you sell it for, after allowable deductions. Unlike your main home, buy-to-let properties do not benefit from Private Residence Relief, so the full gain is potentially taxable.
The current CGT rates on residential property are 18% for basic-rate taxpayers and 24% for higher-rate and additional-rate taxpayers. Your gain is added to your other income for the tax year to determine which rate applies — a large gain could push you from the basic rate into the higher rate band.
Calculating Your Gain
Start with the sale price and deduct the original purchase price, purchase costs (stamp duty, legal fees, survey costs), selling costs (estate agent fees, legal fees), and the cost of any qualifying improvements you have made. Qualifying improvements are capital works that add value — such as extensions, new kitchens, or structural repairs — not routine maintenance.
You can also deduct your annual CGT allowance, which shelters a portion of your gain from tax. The current allowance has been reduced significantly in recent years, so it provides less relief than it once did. Keep detailed records of all purchase, improvement, and selling costs throughout your ownership to maximise your deductions.
Reporting and Payment Deadlines
Since April 2020, UK residents must report capital gains on UK residential property and pay the estimated CGT within 60 days of completion. This is done through HMRC's Capital Gains Tax on UK Property service, separate from your annual self-assessment tax return.
You must still include the gain on your self-assessment return for the tax year, where any adjustment to the CGT amount will be calculated. Failing to report and pay within the 60-day window can result in penalties and interest charges, so factor this obligation into your timeline when planning a sale.
Strategies to Reduce CGT
Legitimate strategies to minimise your CGT liability include transferring the property to a spouse or civil partner before sale (to utilise their CGT allowance and potentially lower tax rate), timing the sale to fall across two tax years, and ensuring all allowable costs are properly documented and claimed.
If you lived in the property as your main residence at any point, you may qualify for partial Private Residence Relief, which can significantly reduce the taxable gain. The rules are complex and depend on when you lived there, so professional tax advice is strongly recommended before selling.
Some landlords choose to hold properties within a limited company, where gains are subject to corporation tax rather than personal CGT. This can be beneficial, but extracting the proceeds from the company still involves tax considerations. Take specialist advice before restructuring your holdings for tax purposes.
Important: Your home may be repossessed if you do not keep up repayments on your mortgage. There will be a fee for mortgage advice. The actual rate available will depend on your circumstances. Think carefully before securing other debts against your home.