SDLT1 is the paper Stamp Duty Land Tax return you send to HMRC by post when you buy land or property in England or Northern Ireland and aren't using a solicitor, agent or conveyancer to file online. It has to reach HMRC, with any tax, within 14 days of the effective date of the transaction, which is usually completion, even if there's no tax to pay. You order the form from HMRC; it comes printed with its own Unique Transaction Reference Number.
Everything below comes from GOV.UK's guidance on sending an SDLT return, completing the SDLT1, checking whether you need a return and late penalties, as of October 2026.
Do you need to send a return at all?
| You usually need a return if | You usually don't if |
|---|---|
| You buy a freehold property | No payment was made |
| You buy a leasehold, depending on what you pay | The property was left to you in a will |
| You take over a property and pay for it or take on a debt, such as a mortgage | It transferred because of divorce or dissolution of a civil partnership |
| The price or value is £40,000 or more | The price or value was £39,999 or less |
These thresholds are as of October 2026. The rates themselves are covered in the Stamp Duty Land Tax guide; this page is about the return.
SDLT1 on paper or a return filed online?
If a solicitor, agent or conveyancer represents you, they should file online through HMRC's Stamp Taxes Online service or approved software, and HMRC rejects printed copies of online returns. If you're not represented, you must use the SDLT1 paper return. Either way, you stay responsible for HMRC getting the return on time and correct.
The 14-day deadline and the effective date
The effective date is usually the date the purchase completes. It can also be the date the contract is 'substantially performed', which happens when you:
- pay most of the purchase price, normally 90% of the payment
- take possession of the property
- make the first payment of rent
Here's the point that catches people buying on their own: the clock runs from that date, and HMRC must receive the form by day 14, not just have it posted. GOV.UK says to allow at least 3 working days for post, and you need to order the paper form in time first. In practice, order the SDLT1 before completion, not after.
Late filing penalties, as of October 2026
| When HMRC gets the return | Penalty |
|---|---|
| Up to 3 months after the filing date | £100 fixed penalty |
| More than 3 months after | £200 fixed penalty |
| More than 12 months after | A fixed penalty plus a tax-based penalty of up to the full tax due |
Tax paid late also carries interest from the day after it was due until you pay. You can appeal a penalty if an unforeseeable event or one beyond your control stopped you filing.
How to fill in the SDLT1 so it isn't rejected
The SDLT1 is read by a scanner, so HMRC's completion guide asks you to:
- Use only the official HMRC print of the form; you can't use photocopies for different transactions.
- Write inside the boxes in black ink, in capitals, with a space between words.
- Mark 'X' in boxes where you have a choice, and don't use correction fluid; start a new form if a mistake can't be corrected clearly.
- Leave boxes blank if they don't apply, unless told to enter '0', and don't use symbols such as currency signs or slashes.
- Answer the questions most often missed: 4 (effective date), 28 (address of the land), 29 (local authority number), 54 (purchaser 1 surname or company name), 56 (purchaser 1 address) and 73 (declaration).
- Answer only one of questions 49, 50 and 51: National Insurance number and date of birth, VAT registration number, or company or partnership Unique Taxpayer Reference.
Extra forms you may need
| Form | When |
|---|---|
| SDLT2 | More than 2 buyers or sellers |
| SDLT3 | Freehold or other transactions involving more than one property, or more space for the address |
| SDLT4 | Leases, mixed use or non-residential property, multiple properties in a lease, or a company as purchaser |
For an additional residential property at the higher rates, the guide says to enter code 04 at question 1, whether or not you expect to claim a refund.
After you post it
- Send it to BT Stamp Duty Land Tax, HM Revenue and Customs, BX9 1LT, with no other correspondence enclosed.
- Pay using the UTRN printed on your form.
- HMRC sends an SDLT5 certificate as proof, or form SDLT8 if anything is missing or unclear.
- Send the SDLT5 and any other SDLT forms to HM Land Registry with your application to register the property.
If you're buying a property to let, keeping the SDLT5 with your purchase records helps later; landlord accounting software can store it with the rest.
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The verdict
Most buyers never see an SDLT1 because their conveyancer files online. If you're buying without one, order the paper form before completion, fill it in by hand in black capitals, and post it so HMRC has it within 14 days of the effective date, even if no tax is due. Keep the UTRN and the SDLT5: you'll need both to pay and to register the property.
Frequently asked questions
What is an SDLT1 form?
It's the paper Stamp Duty Land Tax return you post to HMRC when you buy land or property in England or Northern Ireland and aren't represented by someone filing online.
When must the SDLT1 be sent?
HMRC must receive the return, and any tax due, within 14 days of the effective date of the transaction, even if no tax is owed.
What is the penalty for a late SDLT return?
A fixed penalty of £100 up to 3 months late, £200 after that, and a tax-based penalty of up to the full tax due on top if it's more than 12 months late, as of October 2026.
Can I photocopy an SDLT1?
No. GOV.UK says you can't use photocopies of the SDLT1 for different transactions, because each form is printed with its own UTRN.
Do I need an SDLT1 if the property cost less than 40,000 pounds?
Usually not. GOV.UK says a return generally isn't needed where the price or value was £39,999 or less, as of October 2026.
Where do I send the SDLT1?
By post to BT Stamp Duty Land Tax, HM Revenue and Customs, BX9 1LT.
