Why do Nationwide and Halifax give different house prices?

Why does each house price index show a different number?

Each index is built from a different set of homes, measured at a different point in the selling process. A house price index is a regular report that tracks the average price of homes across the UK. Because one report looks at prices when a seller first lists, and another looks at prices only once a sale has legally completed months later, they are describing different moments in time and different groups of buyers.

Rightmove measures asking prices, which is what sellers hope to get on the day they list. Nationwide and Lloyds each use mortgage approvals from their own lending, so they only see buyers who borrowed from them, and they exclude cash buyers entirely. Zoopla uses sales that have been agreed. HM Land Registry, reported through the UK House Price Index, uses sales that have fully completed and lags the market by around two months as a result.

From July 2026 the Halifax House Price Index was renamed the Lloyds House Price Index. The name changed but the method did not, so the figures continue the same series.

Can two indices disagree about direction, not just level?

Yes, and in September 2026 they did. On 7 September 2026 Lloyds reported UK house prices in August 2026 at £298,468, down 0.2% on the month and down 0.4% on the year, which was the first annual fall its index had recorded since November 2023. Nationwide, measuring the same August, reported £275,465 and annual growth of 1.6%.

The two readings are £23,003 and two percentage points apart for the same month in the same country. Neither is an error. Lloyds is describing the homes Lloyds and Halifax lent against in August, and Nationwide is describing the homes Nationwide lent against, and those are different buyers paying different prices in different places. Amanda Bryden, Head of Mortgages at Lloyds, described average prices as having stayed relatively stable for almost two years, moving within a narrow range.

• A disagreement between two lender indices in one month is normal, because each has a sample of a few thousand of its own approvals rather than the whole market.
• Single month movements in any index are noisy, which is why the indices themselves publish three month and annual comparisons alongside.
• When two measures point opposite ways, the honest reading is that the market is flat rather than that one of them is lying.
• The direction that matters to you is the one in your own postcode, which no national index reports.

Which house price index is the most accurate?

None of them is wrong, and none is the single truth, because they answer different questions. The UK House Price Index, built on completed HM Land Registry sales, is the most complete because it counts every sale including cash buyers, but it lags by around two months. Rightmove is the earliest signal because it captures seller intentions the moment a home is listed, but asking prices are hopes, not results.

• For the earliest read on seller confidence, watch Rightmove asking prices, which fell 2.0% in August 2026, the largest August drop since 2018.
• For a fast monthly steer on lending and buyer activity, watch Nationwide and Lloyds, and read them together rather than separately.
• For the most complete official record of what homes actually sold for, watch the UK House Price Index and accept the two month lag.
• For what your own home is worth, none of the above, because none of them has seen it.

What does this mean for what my home is worth?

It means a national average is the wrong tool for pricing your specific home. These indices blend a one bed flat in Sunderland with a five bed house in Surrey, so the average tells you about the country, not your street. Your home's value is set by what similar homes near you have recently sold for, the condition and layout of your property, and what buyers in your area will pay today.

The spread within a single index makes the point. In the Lloyds figures for August 2026, while the UK annual change was minus 0.4%, Northern Ireland recorded annual growth of 7.4%. One country, one month, one index, and a difference of nearly eight percentage points between the national number and one of its own regions.

ValuQ is the platform that gives UK homeowners free, side-by-side property valuations from competing local estate agents, without handing over your details until you choose to. Seeing several local valuations next to each other, each backed by the agent's own comparable sales, tells you far more about your home than any national headline number ever can.

A national average prices the country. Only a real valuation prices your home.

The practical takeaway for a seller is straightforward. Use the indices to understand the direction of the market, not to set your price. When you are ready to know what your own home is worth, get real valuations from local agents who can point to the actual sales behind their number.