BoughtWell
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How BoughtWell works

Our methods, our measured accuracy and how fresh every data source is. Linked from every “How did we get this figure?” panel.

The method in four steps

  1. STEP 1
    Match

    Every sale is matched to its energy certificate for size and type.

  2. STEP 2
    Index

    Past sales are adjusted to today with the House Price Index.

  3. STEP 3
    Compare

    The closest sales are weighted: same building first, then street.

  4. STEP 4
    Check

    A model trained on 9.5 million sales checks the figure and sets the range.

London valuation accuracy

Tested on sales our model had never seen, once, then published.

Results published in November.

We publish one clean test, run once on sales the model has not seen. Until then we show no accuracy figures. Where evidence is thin we say “not enough evidence” rather than guess.

Data freshness

What every number is built on, and when we last updated it.

  • Land Registry salesto 28 Aug 2026Up to date
  • Energy certificates (EPC)to 30 Sept 2026Up to date
  • House Price IndexAug 2026Up to date
  • Listings and price cutschecked 2 hours agoUp to date
  • Planning decisionsto 21 Oct 2026Up to date
  • Registered leasesnot yet loadedComing soon