How BandCheck works — our data, sources and methods

Our principles

We publish data, not opinions. Three rules govern everything on the site:

1. Every number traces to a named, official source. No figure is invented or “modelled” without the inputs and method shown.
2. Estimates are labelled as estimates. Some numbers — potential refunds, “likely overbanded” counts, illustrative revaluations — are our calculations on top of official data. We never present an estimate as a published fact.
3. Aggregate on open surfaces; personal stays private. Area-level figures (this site, our embeds, our data feed) use open government data only. A check of your specific property's band uses a separate licensed source and happens only inside the on-site checker.

Where the data comes from

All sources published under the Open Government Licence v3.0, covering England & Wales (ASHE: UK).

How each figure is calculated

Challenge and band-review success rates (FY2023-24)

Taken directly from the VOA's published national outcomes, not summed from the per-authority table (which over-counts because 2023-24 spans the April-2023 local-government reorganisations). Of 39,590 challenges resolved that year, 27% resulted in a band reduction and under 1% in an increase. On band reviews — the route most households use — 41% (4,960 of ~12,000 resolved) resulted in a reduction and under 1% (10 cases) in an increase. Per-authority pages show that authority's own resolved-challenge outcomes; small authorities where the VOA suppresses low counts fall back to the regional figure.

Most-common band and band distribution

Straight from the VOA Council Tax stock data for the area — the share of dwellings in each band A–H, and the modal (most common) band.

Band-D charge (2026-27)

The total Band-D council tax for the area, including all major precepts — for London boroughs this includes the Greater London Authority precept; for areas with police, fire, or parish precepts, those are included too. We deliberately use the all-in figure so charges are comparable across the country.

“Likely overbanded” and estimated overpayment (estimate)

Derived from the local band distribution against national averages, then expressed as homes that may be in too high a band and the annual sum that could represent. This is a screening signal, not a verdict on any individual home — labelled an estimate wherever shown.

Estimated refund / reclaim (estimate)

A band-step saving multiplied by the number of years eligible for backdating. The band steps are fixed statutory ratios; the £ figure uses the area's Band-D charge. Always shown as an estimate and a prompt to check, never a promise of a specific sum.

Effective council-tax rate / fairness (estimate)

The area's typical annual bill (Band-D × the statutory ratio for the most-common band) divided by the local median home value from Land Registry sales. Across England and Wales this varies roughly ten-fold — post-industrial Wales and the North pay far higher effective rates than prime London. It is an explainable construction on official inputs, labelled aggregate and estimated.

1991 “time machine” (illustrative)

English council tax bands are still based on April 1991 values. We apply the fixed statutory 1991 band brackets (England: Band A ≤ £40,000 … Band H > £320,000; the equivalent 2003 scale for Wales) against today's median local price to show how far values have moved. Illustrative, not a revaluation.

Revaluation model (illustrative — not a forecast)

A revenue-neutral illustration of which way an area's typical home would move if bands were re-cut on today's values. It is explicitly a model, not a prediction of government policy.

£/m² and typical home (EPC-derived)

Sale price divided by EPC-recorded floor area. EPC floor areas are assessor estimates, so we treat £/m² as a proxy and label it EPC-derived.

Important caveats

• Rounding and suppression. VOA counts are rounded to the nearest 10, and counts under 5 are suppressed (shown as “-”). Small-area figures inherit a regional fallback rather than a misleadingly precise number.
• Two appeal datasets, not summed. VOA challenge counts (counted by the year a proposal resolved) and Valuation Tribunal Service data (counted on receipt) are not directly comparable. We keep them in separate, clearly-labelled panels and never add them together.
• Savings are derived, not published. The VOA publishes outcome counts, not pounds saved. Any “£ returned” figure is our estimate (reductions × an average band-step saving) and is labelled as such with the method shown.
• Data vintage. The latest VOA challenges release covers FY2023-24. A later release was postponed pending the VOA's new operating system; we label the year on every figure and do not imply it is current-year.
• Coverage. Per-area figures cover England and Wales. Scotland's per-address bands are not in our data source, so Scottish checks use a manual-entry path and the area signal is weaker there — we say so rather than bluff.

Suggested citation

BandCheck, “How BandCheck works — data, sources and methods,” bandcheck.co.uk/methodology, 2026. Underlying data: Valuation Office Agency, HM Land Registry and the Office for National Statistics, Open Government Licence v3.0.

Frequently asked questions