Methodology
Data Freshness
A price you cannot date is a price you cannot rely on. Providers run offers, adjust delivery charges, and change consultation fees without notice, and a comparison built on figures gathered weeks ago is worse than no comparison at all: it looks authoritative while being wrong.
So we treat the age of a price as part of the price. Every figure carries the date it was last verified, that date is shown to you rather than held internally, and how recent it is affects where a provider sits in the table.
How we keep prices current
Three commitments: the date is shown, the check is repeated, and recency carries weight in the ranking.
Shown on every row
Timestamp transparency
Every listed price displays the exact date it was verified against the provider’s own site. If a figure is older than you are comfortable acting on, you can see that before you click rather than afterwards.
Repeated on a cycle
Monitoring cycle
Prices are re-checked on a regular cycle against the provider’s live pages, not against a feed handed to us once. Where a price moves between checks, the correction lands at the next check, or sooner if a reader reports it.
Affects position
Recency in the ranking
Where two providers reach an identical calculated total, the one verified more recently ranks higher. Recency is the second criterion in the sort, so a stale price cannot hold a joint-top position against a freshly confirmed one.
Freshness states
Every price and verification record carries one of six states. Each state is shown with an icon and descriptive text, never by colour alone, so the meaning survives for readers who cannot distinguish the colours and for anyone using a screen reader.
Current
Verified within the review window. The figure is as recent as our cycle allows and is used in the tables without qualification.
Review due
Past the review threshold but not yet stale. The record is flagged for re-checking and stays in the tables while that happens.
Stale
Past the stale threshold. The figure carries a prominent warning wherever it appears, so it is never presented as though it were current.
Expired
Too old to stand behind. The figure is withheld rather than shown with a caveat, because a number on screen reads as a claim regardless of what sits next to it.
Unverified
Supplied or observed but not yet confirmed against the provider’s own page. An unverified figure is never used to rank a provider.
Suspended
Held out of comparison pending a check, for example while a registration change is confirmed. The provider does not appear in the tables while its record is suspended.
Thresholds
The exact thresholds are still being set
The number of days that separates current from review due, and review due from stale, is being confirmed and will be published here once it is fixed.
What is already fixed is the behaviour at each threshold: records past the review threshold are flagged for re-checking, and records past the stale threshold carry a prominent warning or are withheld from comparison entirely. We would rather publish the rule with a number still pending than publish a number we have not agreed to hold ourselves to.