Recovering Incorrect SDLT Payments

Overpayment Overview and Scale

SDLT overpayments are far more common than most buyers realise. HMRC statistics show that approximately £1.2 billion was repaid to taxpayers in FY2023-24, representing a significant proportion of total SDLT receipts. The complexity of the SDLT rules — particularly around reliefs, property classification, and multiple transactions — means that even experienced solicitors occasionally calculate SDLT on an incorrect basis.

Two statutory routes exist for recovering overpaid SDLT: the 12-month amendment window under FA 2003 Sch 10 para 6, and the 4-year overpayment relief under FA 2003 Sch 10 para 34. The correct route depends on how much time has passed since the SDLT1 was filed. Our complete refund guide provides a full overview of all refund scenarios.

The 12-Month Amendment Window

FA 2003 Sch 10 para 6 provides that a buyer may amend their SDLT return at any time within 12 months of the date it was filed. This is the most straightforward mechanism for recovering overpaid SDLT — the buyer (through their solicitor or directly) submits an amended SDLT1 showing the corrected tax position. If the amendment results in a lower tax liability, HMRC repays the difference.

The 12-month window runs from the filing date of the original return, not from completion. Since the SDLT1 is typically filed within 14 days of completion, in practice the amendment window is approximately 12 months after completion.

The 4-Year Overpayment Relief

FA 2003 Sch 10 para 34 provides a separate claim mechanism for cases outside the 12-month amendment window but within 4 years of the SDLT1 filing date. This "overpayment relief" covers situations where the original return was filed correctly based on the information available, but subsequent events or a revised understanding of the law reveals that less tax was properly due.

Overpayment relief claims are also available where a relief was not claimed at the time of filing but the buyer was entitled to it. For example, if a buyer did not realise they qualified for first-time buyer relief and paid standard rates, they can claim back the difference within 4 years.

SDLTM50600-50700 in HMRC's Stamp Duty Land Tax Manual covers the detailed mechanics of overpayment relief claims and the circumstances in which HMRC will and will not accept such claims.

Using the SDLT17 Form

SDLT17 is HMRC's standard form for amending an SDLT return and claiming a repayment. It can be used both for 12-month amendments (para 6) and 4-year overpayment relief claims (para 34). The form requests:

• The Unique Transaction Reference Number (UTRN) from the original SDLT5 certificate
• The original effective date of the transaction (completion date)
• The corrected tax figures (what should have been paid)
• The reason for the amendment (e.g., relief not claimed, incorrect classification)
• Evidence supporting the claim (attached as supporting documents)
• Bank account details for the repayment

SDLT17 can be submitted by post to HMRC's Stamp Taxes team in Birmingam, or by your solicitor / tax agent via HMRC's online service. Electronic submission generally results in faster processing. The refund claim process guide walks through each step in detail.

Using the SDLT60 Form

SDLT60 is a dedicated form for claiming a refund of the additional dwelling surcharge (the 5% higher rate under FA 2003 Sch 4ZA). It is used specifically when a buyer:

• Paid the additional dwelling surcharge at the time of purchase because they owned another residential property
• Has since sold the previous property, qualifying for the replacement main residence exception retrospectively
• Is within the 36-month window from the date of the purchase that attracted the surcharge

The SDLT60 requires evidence of both the original purchase (the SDLT5 UTRN) and the subsequent sale (completion statement for the disposal). HMRC verifies that the replacement main residence conditions in Sch 4ZA para 3 are satisfied before making the repayment.

The 36-month window for SDLT60 claims runs from the effective date (completion date) of the purchase that attracted the surcharge — not from the date of the subsequent sale. Keeping your records is therefore essential to prove both the original payment and the timing of the disposal.

Common Overpayment Scenarios

The following scenarios represent the most frequent sources of SDLT overpayments. If any of these apply to your transaction, you should consider whether a claim is appropriate.

Worked Examples

Example 1: Missed First-Time Buyer Relief — £350,000 Purchase

Example 2: Mixed-Use Misclassification — £600,000 Live-Work Property

Mixed-use cases depend heavily on the specific property characteristics — professional valuation and legal advice is recommended.

Step-by-Step Claim Process

HMRC Response Times

HMRC's Stamp Taxes team handles SDLT amendment and overpayment relief claims. Response times depend on the complexity of the claim and current workloads. As a general guide:

HMRC may request additional information or evidence during processing. Respond promptly to any queries to avoid delays. Do not chase the claim before the minimum processing time has elapsed — HMRC's SDLT helpline can confirm the status after 8 weeks.

When to Seek Professional Help

Not all overpayment claims require professional advice. Simple FTB relief claims and straightforward SDLT60 refunds can often be handled directly by the buyer or their original solicitor. However, professional advice is strongly recommended in the following circumstances:

• Mixed-use or MDR claims: These require legal analysis of the property's characteristics and HMRC's current approach to borderline cases.
• High-value claims (above £50,000): HMRC will scrutinise large claims carefully; specialist SDLT advisers can anticipate and pre-empt queries.
• Claims where HMRC has already enquired: If HMRC has opened a compliance check, do not engage without professional representation.
• Claims near the 4-year deadline: Timing is critical; a specialist can ensure the claim is made correctly and on time.

Specialist SDLT advisers and tax barristers handle these claims regularly. Many work on a contingency or fixed fee basis for clear overpayment claims. Be wary of SDLT reclaim firms that charge high upfront fees for claims that your own solicitor could handle. See our legal guidance on SDLT returns for further context.

Frequently Asked Questions