Offrly Sale Valuation Accuracy Report (2026)
Offrly's accuracy is tracking but not yet published: every BUY valuation is frozen at quarter-end and auto-joined to the eventual HM Land Registry sold price 6 months later. The first published metrics land on 2027-03-30.
Every BUY valuation is sealed at quarter-end — postcode, prediction, timestamp.
Latest valuation per postcode only — nothing counts twice.
~6 months for HMLR to publish the matching sold prices.
Same postcode, sold after the prediction. Ties break closest-by-price — documented, not hidden.
Hit rates, MdAPE, MAE — full distribution, misses included.
How one pair resolves
IllustrativeDeterministic, dated, traceable to a real prediction and a real HMLR row. No human curation anywhere in the join. The numbers here are made up for illustration — no specific home is implied.
0 snapshots sealed so far. This page pools every quarter; the benchmark shows each snapshot alone — dated, immutable.
Open the quarterly benchmark →Once published, a hit rate within ±10% is the share of Offrly estimates that land within 10% of the real sold price — roughly where mainstream postcode-average AVMs report (60–70%). Offrly's difference is architecture: photo-aware comparables and street-level pricing. It is still a market estimate, not a guaranteed sale price — for probate, mortgage or insurance, use a RICS surveyor.
How we measure accuracy
Offrly's accuracy figures are computed against HM Land Registry Price Paid Data — the authoritative record of every residential property transaction in England and Wales, published monthly under the Open Government Licence.
This is a prediction-vs-outcome report rather than a synthetic back-test. Each figure traces back to a real Offrly prediction and a real HMLR sold-price row, with no admin in the loop:
- Every BUY valuation Offrly issues in a given quarter is frozen at quarter-end into an immutable snapshot — postcode, predicted price, timestamp and the confidence band shown with the estimate (a 90% interval since July 2026; earlier valuations displayed a 95% band).
- Across every quarterly snapshot we collapse to the latest BUY valuation per full postcode. A property revalued in a later quarter only contributes its most recent prediction, so the same postcode never lands in the sample twice.
- Six months later, when HM Land Registry has published the matching sold-price data, each surviving valuation is auto-joined to sales on the same full postcode with a sold date after the valuation was made.
- If a postcode has more than one matching sale, the closest-by-price sale is selected — the same tie-break rule used on the per-quarter benchmark. We document it openly rather than hiding it.
- The metrics on this page aggregate every quarterly snapshot into a single lifetime view: hit rate within ±10% and ±20%, MdAPE and MAE.
What's in the report, transparently
- Scope: sale valuations only. Rentals are not included — there's no public sold-price equivalent for rentals to pair them against.
- Ground truth: HM Land Registry Price Paid Data — every arms-length freehold and most leasehold residential sales in England and Wales.
- Licence: Open Government Licence v3.0 — reusable, citable.
- Sample: tracking from day one. 758 BUY valuations issued to date, 0 sealed across 0 quarterly snapshots. The first auto-joined pairs land on 2027-03-30. We publish the denominator so coverage stays auditable from the start.
- Leakage controls: by construction, every prediction was made strictly before its matched HMLR sold date — predictions never see future sold prices.
- Update cadence: a new snapshot freezes at each quarter-end; metrics for that snapshot land six months later as HMLR catches up. The page recomputes on every load.
How we compare to the rest of the market
Mainstream automated valuation models — the postcode-average tools most free portals run on — publish hit-rate-within-±10% figures broadly in the 60–70% band. Offrly's differentiator isn't just the point estimate, it's the model architecture: a photo-aware AI that reads each comparable the way a human analyst would, paired with hyperlocal pricing that resolves down to the street rather than the postcode. Free, no mandatory signup, with the methodology fully auditable on this page.
All accuracy claims age quickly as the market moves. As fresh HMLR data lands and new quarterly snapshots resolve, the figures here update.
For the per-quarter view of the same data, see the sealed quarterly benchmark — each individual snapshot, dated and immutable. Both pages compute their metrics from the same auto-join; this one just pools every quarter so the sample is bigger.
Frequently asked questions
What does 'hit rate within ±10%' mean?
It's the share of Offrly sale estimates that land within 10% of the actual sold price across every valuation we've matched to an HM Land Registry sale. A 60% hit rate means 6 in 10 estimates were within ±10% — an industry-standard way of measuring how close an automated valuation model gets to the true price.
How are predictions paired to HMLR sales?
Every BUY valuation issued in a given quarter is frozen to an immutable snapshot at quarter-end. Across every snapshot we collapse to the latest BUY valuation per full postcode, so a property revalued in a later quarter only contributes its most recent prediction. Six months later, when HM Land Registry has published the matching sold-price data, each surviving valuation is auto-joined to sales on the same full postcode that completed after the valuation date. There is no human review. When a postcode has more than one sale in the window, the closest-by-price sale is selected — the same rule used on the per-quarter benchmark.
Does this cover rentals?
No. The accuracy report is for sale valuations only. There is no public sold-price equivalent for rentals, so we cannot publish a comparable rental accuracy figure honestly.
How is this different from the per-quarter benchmark?
The metrics on this page aggregate every quarterly snapshot into a single lifetime view. The /benchmark URL shows a single quarter's snapshot, sealed and dated. Both pages compute their metrics with the same auto-join — this one just pools the snapshots so the sample is bigger.
Why should I trust these figures more than a marketing claim?
Because the ground truth is HM Land Registry, published under the Open Government Licence — and the pairing is fully automated, with no admin choosing which pairs make the cut. Each figure on this page traces back to a frozen Offrly prediction and the closest-by-price HMLR sold row that followed it on the same postcode.
Should I use an Offrly valuation instead of a surveyor?
No. Offrly estimates are indicative market guidance. For probate, mortgage, insurance or tax-binding figures, use a RICS-qualified surveyor. Offrly is for orientation, negotiation and informal decision-making — not for binding purposes.
Source: HM Land Registry Price Paid Data, licensed under Open Government Licence v3.0. Offrly estimates are indicative market guidance — not regulated valuations and not financial, tax or legal advice.