After months of speculation about possible Stamp Duty reform, today’s 2025 Budget has confirmed that the SDLT system remains unchanged.
For many across the sector this brings relief, but it also raises an important question. If nothing changed today, why did the market slow so sharply while rumours circulated?
The clearest answers come from the Office for Budget Responsibility, whose economic and fiscal outlook explains how Stamp Duty continues to influence behaviour and why uncertainty alone can shift activity across the entire market.
Below is a clear analysis of the most important points.
Stamp Duty continues to suppress mobility
The OBR has reduced its forecast for residential transactions by around one hundred and fifty five thousand a year by 2029. This is a significant adjustment and is not linked to a temporary economic factor. Instead, the OBR attributes part of the reduction to the long term effects of previous increases to Stamp Duty.
Higher SDLT charges discourage households from moving. That behaviour then becomes built into the baseline forecast. In other words, the tax has created a lasting drag on mobility that the Treasury now treats as a structural feature of the market.
This confirms what many professionals observe in practice. SDLT is not simply a tax collected on completion. It is a force that shapes decisions, timing and willingness to move, as reflected in HMRC’s stamp duty statistics.
The new council tax surcharge interacts with SDLT
Although today’s Budget did not change SDLT, it did introduce a new council tax surcharge on homes valued above two million, taking effect from April 2028 on 2026 values.
The OBR expects this surcharge to reduce property values at the upper end of the market. Lower values then feed directly into:
- lower Stamp Duty payments on affected purchases
- lower capital gains tax receipts at the point of sale
- price clustering below key thresholds.
This is set out in the Budget policy costings published by HM Treasury and further assessed in the OBR’s policy costings and behavioural analysis.
This demonstrates a point often overlooked. Even when SDLT rules remain unchanged, tax measures elsewhere in the system can influence Stamp Duty behaviour and revenue.
Policy uncertainty continues to distort behaviour
The OBR also notes that earlier changes to the nil rate threshold created timing distortions in transaction volumes. These distortions continue to influence the current year’s figures.
This is an important reminder that the property market is highly sensitive to SDLT policy movement. Even relatively small adjustments can encourage people to accelerate or delay transactions, and those effects remain visible long after the change has taken place.
This pattern is demonstrated repeatedly in HMRC’s UK property transaction statistics and the OBR’s forecast evaluation reports.
For advisers, solicitors and agents this creates a challenging environment. Decisions often need to be made before the Government has confirmed its intentions. The result is a market that reacts to rumour as much as it reacts to legislation.
Why speculation caused real disruption even though nothing changed
SDLT is a behavioural tax. It affects incentives, timing and the willingness to move. When a tax has that much influence, speculation alone can change the market in real time.
The extended rumour cycle this year led to:
- delayed exchanges
- buyers waiting for potential cuts
- sellers hesitating in case the system changed
- difficulty giving clear advice
- fragile chains held in place for longer than necessary
The fact that the Budget ultimately made no change to SDLT does not undo the disruption already caused. Activity slowed because people feared being caught on the wrong side of a possible reform that never materialised.
What this means going forward
With the Budget now behind us, the position is clearer, but the underlying issues remain.
SDLT continues to:
- reduce mobility
- influence when people choose to buy or sell
- create sensitivity to even small policy adjustments
- generate distortions that remain visible in national forecasts
The new council tax surcharge adds further complexity at the upper end of the market. It does not change SDLT but does influence valuation behaviour and future tax receipts.
For professionals, the picture is unchanged.
SDLT remains a complex and high risk area. It’s long term behavioural effects are now openly acknowledged by the OBR. And the market remains vulnerable to speculation whenever the possibility of reform is raised.
Conclusion
This Budget will be remembered less for the policies introduced and more for the speculation that preceded it. SDLT has emerged unchanged, yet its influence on the property market is clearer than ever.
The OBR’s analysis shows that Stamp Duty is not simply a tax applied at completion. It is a force that shapes behaviour, timing and market confidence. Even without reform, it continues to exert pressure on mobility and pricing. And when rumours spread about possible change, the market reacts instantly.
Understanding these dynamics will be essential for anyone involved in property during the year ahead.
Managing Director at Compass
