The route, stage by stage
| Stage | When | What happens |
|---|---|---|
| Draft list | Late 2027 | Ask the Valuation Office to correct factual mistakes. No formal challenge needed. |
| Bills | March 2028 | Councils issue the first surcharge bills. |
| Initial challenge | 8 months | Challenge the band, or the decision that the home is in scope, with the Valuation Office. |
| Response | Within 4 months | The Valuation Office must reply to the challenge. |
| Appeal | Within 3 months | If you disagree with the reply, appeal to the Valuation Tribunal for England. |
| Later changes | 6 months | After a revaluation or a new banding, a standard 6-month challenge window applies. |
Based on the consultation proposals. You keep paying while a challenge or appeal is running, and are refunded if it succeeds.
Stage one: the draft list
The Valuation Office plans to publish a draft list of homes in scope in late 2027. Under the proposals, owners can then ask it to correct factual inaccuracies that affect the band, and it can correct them without a formal challenge. Correcting a fact is different from disputing the valuation itself, which needs a formal challenge. This is the cheapest and quickest fix, so it pays to know what the facts should be before the list appears.
Stage two: a formal challenge
Because the surcharge is new, owners get an initial 8-month window to challenge. You can challenge the band itself, or the decision that the home is in scope at all. The Valuation Office then has four months to respond.
Stage three: the Valuation Tribunal for England
If you are not satisfied with the response, you have three months to appeal to the Valuation Tribunal for England, the independent body that already hears council tax and business rates appeals. It can decide disputes about banding, liability and changes to the list.
Challenging who pays
Disputes about who is liable, for example between a freeholder and a leaseholder, or between trustees, go to the council rather than the Valuation Office. The council is proposed to have two months to respond. You would then have two months to appeal to the tribunal, or four months if the council does not respond at all.
What makes a challenge stand up
A challenge is an argument about value, and value is argued with evidence. The strongest cases usually rest on one or more of these:
- a factual error in the Valuation Office's record, such as floor area, rooms, outside space or tenure
- better comparable sales from around 2026 than the ones the Valuation Office relied on
- features that lower value and that a buyer in 2026 would have taken into account: defects, noise, poor access, overlooking, a short lease
- a home that sits close to a line, where a modest difference in value changes the band
What does not work is arguing about the policy itself, or pointing to what the home is worth today rather than in 2026.
A challenge is not a way round the tax. It is the route the proposals give every owner to make sure the band matches the evidence, so nobody pays more than they legally should.
How we help
We prepare the evidence before the draft list, check your entry when it appears and, if a challenge is needed, explain what we would do, what it costs and the risks before you decide, working with a qualified tax adviser and property surveyor. We only act for you with your written authority and an agreed scope of work. If a case goes to the tribunal, we will tell you what it involves and what it is likely to cost before you decide. The dates on this page are proposals and may change until the rules are made.
Challenge questions
Can I challenge my mansion tax band?
Yes. Under the proposals, owners get an initial 8-month window to challenge their band once the surcharge starts, and a standard 6-month window after later changes such as a revaluation. If the Valuation Office does not agree, you can appeal to the Valuation Tribunal for England.
Do I have to keep paying while I challenge?
Yes. The proposals say owners must keep paying while a challenge or appeal is under way. If it succeeds, the overpayment is refunded.
What if I think someone else should be paying?
That is a liability challenge, made to the council rather than the Valuation Office. The council is proposed to have two months to respond, and you could then appeal to the Valuation Tribunal.
Last checked against the government's Budget documents and consultation response on 30 October 2026. The surcharge is being legislated in the Finance Bill 2026-27 and is not yet law. Some detail is still to come in regulations.