You must tell HMRC about any errors or changes to your Stamp Duty Land Tax (SDLT) return using the specific routes HMRC sets out, and in many cases within 12 months of the original filing date. This usually means either calling the SDLT helpline for minor corrections or writing to HMRC and sometimes submitting a fresh SDLT return for more substantial changes.legalforms.
Overview of SDLT amendments
Once you have filed an SDLT return, HMRC allows you to correct mistakes, but the process depends on the type of change and how long ago the return was filed. The core rule is that you normally have 12 months from the filing date to amend your return, with different procedures for minor, small and substantial changes.
HMRC defines the filing date as 14 days after the effective date of the transaction, which is usually completion for a standard purchase. Separate guidance applies if the transaction is in Scotland or Wales, where different land tax regimes operate.
When you can amend an SDLT return
You generally have 12 months from the filing date to ask HMRC to change your SDLT return. Within this window you can correct a range of errors, but HMRC distinguishes between amendments that can be dealt with by phone and those that must be made in writing or accompanied by a new return.
If HMRC has opened a compliance check, you can still submit an amendment, but the change only takes effect once the check closes and HMRC confirms whether your amendment has been accepted.
Minor changes by phone
Minor changes are straightforward corrections that do not result in an SDLT refund. Examples include fixing vendor details, correcting buyer details on certain questions of the SDLT1 paper return, spelling mistakes in the property address, the title number, and obvious errors in the purchase price or tax calculation.legalforms.
You can also correct the effective date of the transaction, provided the new date does not mean HMRC received the return before the effective date. For these minor amendments you call the Stamp Duty Land Tax helpline, which is HMRC’s main contact point for SDLT queries.
Information you need before calling
HMRC expects you to have the agreement of all buyers where there is more than one, because the amendment affects their legal position. You must also quote the Unique Transaction Reference Number (UTRN), which appears on the SDLT5 certificate for online filings or on the paper return and the certificate HMRC issued, and you should be ready to explain exactly what needs to change.
During the call HMRC will confirm whether they can make the change and whether the correction means further SDLT is due, in which case you must pay the additional tax immediately to avoid interest and possible penalties.
Small changes by letter
Small changes are amendments that are more than a trivial correction but still do not require a full new return. HMRC treats adding a title number, adding or removing a buyer, or including another property in the transaction as small changes.legalforms.
For these you must write to HMRC quoting the UTRN and giving full details of the changes requested. Where there is more than one buyer, or buyers are being added or removed, the letter must confirm that all buyers agree to the amendment and each buyer should sign to evidence that consent.
Letters about small changes, together with a copy of the contract, should be sent to the BT Stamp Duty Land Tax office at HM Revenue and Customs, BX9 1HD. HMRC will respond in writing to confirm either that the change has been made or that further steps are needed, including any extra SDLT payable.
Substantial changes and new returns
Substantial changes are amendments that alter the core details of the transaction, rather than tidying up a minor error. HMRC treats changing the buyer’s name beyond a simple spelling correction, changing the property details other than minor address spelling, or moving the effective date to a point after HMRC received the original return as substantial.
In these cases you must both write to HMRC and submit a new SDLT return with the correct information. Your letter must explain why a new return is needed, quote the UTRNs for both the incorrect and correct returns, and include signatures from all buyers named on both returns, together with any supporting evidence.
The letter, copy of the original return and evidence go to BT Stamp Duty Land Tax, HM Revenue and Customs, BX9 1HD, while a new paper SDLT1 return is sent to BX9 1LT or an electronic replacement is filed online or via recognised commercial software, typically by your solicitor or conveyancer.
Amending during an HMRC compliance check
If HMRC opens a compliance check into your SDLT return, they will write to you naming the officer dealing with the case. You can still tell HMRC about errors or omissions, but you should contact the person named on the compliance check letter rather than using the general helpline.
Any amendment you make during a compliance check will only take effect once HMRC issues a closure notice and confirms whether your changes have been accepted or rejected. If HMRC concludes that the amendment is incorrect, they will instead adjust the return based on their findings and may charge additional SDLT and penalties.
Duplicate or mistaken returns
HMRC sometimes receives returns that were not required or duplicate SDLT returns for the same transaction. If you realise you have filed a return in error or sent duplicate returns, you must write to HMRC explaining whether the transaction actually needed a return and, if there was more than one, listing the UTRNs for all returns.legalforms.
The letter should also state whether the SDLT5 certificate has been used to register the transaction with HM Land Registry and include any evidence if the duplicate returns differ. You send this letter and supporting documents together to BT Stamp Duty Land Tax, HM Revenue and Customs, BX9 1HD.
If HMRC has charged a penalty for a mistaken or duplicate filing, you can appeal by writing within 30 days of the penalty notice, explaining your reasonable excuse, and in many cases using form SDLT46. Appeals are usually sent to the same BX9 1HD address and must normally be made within the 30 day window to be considered.
Mistakes more than 12 months old
HMRC allows you to report mistakes even where the normal 12 month amendment window has passed, but the process is more formal. For minor mistakes such as spelling corrections to a buyer’s name, you send a letter describing the correction together with a copy of the original return to the BT Stamp Duty Land Tax office at BX9 1HD.
For any other mistake beyond the 12 month period, you must write to HMRC explaining the error, how and why it occurred, and include a copy of the original return. You will also need to file a new SDLT return, either online or by post, and HMRC may still consider refund claims where the mistake caused you to overpay SDLT.
If you have underpaid SDLT
If you discover that you have underpaid SDLT, HMRC expects you to contact the Stamp Duty Land Tax helpline as soon as possible. You should pay the additional tax promptly, quoting the UTRN, to minimise interest and reduce the risk of behavioural penalties for careless or deliberate underpayment.
Failing to correct an underpayment or leaving it until HMRC identifies the issue may result in penalties and interest, particularly if a compliance check is already under way. Early disclosure and cooperation with HMRC typically lead to a more favourable penalty position.
How UK property tax accountants help with SDLT amendments
UK property tax accountants provide practical support at every stage of correcting an SDLT return, ensuring you follow HMRC’s rules and time limits correctly. As specialist advisers, we can review the original transaction, identify whether your issue is a minor, small or substantial change, and recommend the most efficient route, whether that is a helpline call, a detailed letter or a full replacement return.
We draft clear amendment letters that meet HMRC’s expectations, including the right UTRNs, explanations and buyer signatures, and we coordinate with your solicitor or conveyancer to submit any new SDLT returns online or by post. Where penalties or interest have been charged, we assess whether there is a reasonable basis to appeal, prepare SDLT46 appeals within the 30 day deadline and represent you in dealings with HMRC or the tribunal where necessary.
FAQs
How long do I have to amend my SDLT return
In most cases you have 12 months from the filing date, which is 14 days after the effective date of the transaction, to amend your SDLT return.
Can I correct my SDLT return by phone?
Yes, minor corrections that do not lead to a refund, such as spelling errors or simple buyer and property details, can typically be made by calling the SDLT helpline with your UTRN and buyer agreement.
When do I need to file a new SDLT return?
You must file a new SDLT return if there is a substantial change, for example a different buyer, a significant change in property details or a new effective date that falls after HMRC received the original return.
Can I amend my SDLT return after HMRC starts a compliance check?
You can still submit an amendment, but you must deal with the named officer on the compliance check letter and your changes only take effect once HMRC issues a closure notice and confirms its decision.
How do I appeal an SDLT penalty?
You usually have 30 days from the penalty notice to appeal in writing, explaining your reasonable excuse and often using form SDLT46, which is sent to the BT Stamp Duty Land Tax office at BX9 1HD.
