What Records to Keep for Capital Gains Tax

Keeping accurate records is essential when it comes to Capital Gains Tax. You need to maintain detailed documentation about your assets from the moment you acquire them until you sell or dispose of them, and for several years afterwards. Without proper records, you won't be ab...

Introduction

What records you need to keep

When you buy or acquire an asset, you should keep records showing:

The date you acquired it
How much you paid for it (including purchase costs like solicitor's fees, estate agent fees, Stamp Duty, and any commission)
Receipts and invoices for the purchase

If you inherited the asset or received it as a gift, you need to keep:

Records of what the person who gave it to you originally paid for it
The date they acquired it
Any valuation documents showing its market value when you received it

Records of improvements and costs

During the time you own an asset, you should keep evidence of any money spent that added value or enhanced it. This includes:

Receipts for improvements to property (such as an extension or conversion)
Professional fees for valuations
Costs of defending your ownership rights

Keep in mind that routine maintenance and repairs don't count as improvements for Capital Gains Tax purposes.

Records when you sell or dispose of an asset

When you sell, give away, or otherwise dispose of an asset, keep documentation showing:

The date of disposal
The sale price or market value (if you gave it away)
Costs of selling (such as estate agent fees, solicitor's fees, and advertising costs)
Any correspondence with buyers or advisers

Records for specific types of assets

Property records

For property, you need to keep:

Purchase and sale contracts
Completion statements
Land Registry documents
Records of how long you lived in it as your main home (if applicable)
Evidence of any periods you let it out
Records of any business use

Shares and investments

For shares, you should maintain:

Contract notes from when you bought and sold
Dividend vouchers and statements
Records of any bonus or rights issues
Details of any share reorganisations or takeovers
Records showing shares held in ISAs or PEPs (which are exempt from Capital Gains Tax)

Personal possessions

For items like jewellery, art, or antiques worth £6,000 or more:

Purchase receipts
Valuations
Sale documentation
Insurance valuations (these can help prove value but aren't definitive for tax purposes)

Special situations requiring additional records

Jointly owned assets

If you own an asset with someone else, keep records showing:

Your ownership share
How the purchase price was split
How disposal proceeds were divided

Assets received from your spouse or civil partner

When your spouse or civil partner gives you an asset, there's no immediate Capital Gains Tax. However, if you later sell it, your gain is calculated from when they originally acquired it. You must keep:

Records of what they paid for it
The date they bought it
Any costs they incurred

This is particularly important because you're responsible for keeping these records, not your spouse.

Gifts to charity

If you give an asset to charity, keep records showing:

The charity's details and confirmation they're registered
The market value at the time of the gift
Any amount the charity paid you (if it was a discounted sale)

How long to keep records

You must keep your Capital Gains Tax records for at least 12 months after the 31 January Self Assessment deadline following the tax year in which you disposed of the asset.

For example, if you sold an asset in the 2025/26 tax year (which runs from 6 April 2025 to 5 April 2026):

You'd report it in your 2025/26 Self Assessment tax return
The deadline for this return is 31 January 2027
You must keep records until at least 31 January 2028

However, it's often wise to keep records longer, especially for assets you own for many years or if there are complex calculations involved.

Why accurate records matter

Without proper records, you cannot:

Calculate your gain accurately
Claim all the costs and reliefs you're entitled to
Prove your calculations to HMRC if they enquire

Poor record-keeping can lead to:

Paying more tax than necessary (if you can't prove your costs)
Penalties from HMRC (if they believe you haven't taken reasonable care)
Stress and additional accountancy fees when trying to reconstruct information

What to do if you've lost records

If you've lost paperwork, you may be able to obtain:

Copy contracts from your solicitor
Duplicate statements from your bank or investment platform
Valuations from professional valuers
Land Registry documents

The sooner you organise missing documentation, the easier it will be to obtain.

Current tax-free allowance

For the 2025/26 tax year, the Capital Gains Tax allowance is £3,000 (or £1,500 for trusts). You only pay tax on gains above this amount.

Even if your total gains are below £3,000, you may still need to report them to HMRC if the total proceeds from selling your assets exceeded £50,000 in the tax year.

Sources

Capital Gains Tax: what you pay it on, rates and allowances

This article provides general guidance based on current HMRC rules. For advice specific to your situation, speak to your accountant.