About

What this tool is, how it knows what it knows, and where to look when you don't trust what you see.

About this browser

A versioned, paragraph-level browser for the UK Immigration Rules. Each appendix is readable at any tracked effective date; toggling Show changes since previous version reveals word-level differences between adjacent versions, and Show cumulative annotations renders amendments in legislation.gov.uk style with footnoted insertion dates.

Sources and copyright

The Rules text is Crown copyright, sourced from the official gov.uk publication. The structured diffing, paragraph-level versioning, and annotation work are by Free Movement.

The model — Statements of Changes as truth, archive verifies

The Immigration Rules change when a Statement of Changes (SoC) is laid before Parliament. Each SoC carries a commencement date and a list of operations on the existing Rules text — insert this paragraph, delete that one, substitute these words. The engine compiles those operations and reconstructs the Rules at each commencement date.

The gov.uk archive (UK Government Web Archive snapshots of gov.uk/guidance/immigration-rules and its appendix pages) is the second leg. The engine compares its reconstruction against the nearest archived snapshot and surfaces divergences — so when text shown here disagrees with the published version, you see it side-by-side rather than having to spot it for yourself.

How far back — and how confident

The reconstruction runs from the original 1994 Rules (HC 395) to the present. How far we can stand behind a given paragraph depends on whether a gov.uk archive capture exists to confirm it at that date.

Confirmed. Where the gov.uk archive captured the Rules around a date, the engine compares its reconstruction to that capture. Agreement is shown as Confirmed; a difference is shown side-by-side with a word-level diff, or — for a known archive extraction defect — the Statement-of-Changes version with a footnote. Captures are dense from the late 2000s onward and reach back to 2004 for most Parts.
Reconstructed, not yet confirmed. For earlier dates the archive is sparse or absent, so a paragraph stands on the Statements of Changes alone and is tagged by how it was derived — 1994 baseline (unchanged from HC 395), mechanically applied (parsed from a Statement) or structurally recovered (a series rebuilt from a Statement's text). The text is reconstructed and dated from the Statements; it is simply not independently confirmed against an archive capture.

The Statements of Changes are always the authority for the position on an exact date. The gov.uk archive — captured only at intervals, and able to lag a commencement — is what we check the reconstruction against, and link out to, rather than the last word on the law.

The coverage page sets this out per Part and Appendix: how many dated versions we hold, how much is confirmed against the archive, and where the thin patches are.

What this tool does not tell you

What the law currently is. Everything here is a historical snapshot at a commencement date. Use it to see what the Rules said then. For "what they say now", check gov.uk.
Which specific paragraphs are wrong on any given date. Reconciliation against the archive is high where captures are dense but not 100%, and thinner for the earliest years. The coverage page shows where accuracy is strongest and where to look harder.
Anything resembling legal advice. A practitioner who knows what they're doing can read history off this tool faster than a typeset PDF. It is not a substitute for judgement.

Honest residue

The known imperfections you may notice:

14 unattributed change points. SoC commencement labels on the slider are correct in ~98% of cases; a handful of class-4 residue points show "A change took effect on this date — not yet attributed" because the Statement that commenced the change couldn't be identified deterministically. The text shown is still the reconstruction at that date.
Appendix O / Q extraction residue. Cosmetic artefacts from the HTML parser on those two appendices. The text is the genuine source structure — formatting may look slightly off in places. Reported to Colin if you spot something material.
Pre-2004 dates are reconstruction-only. No consolidated gov.uk archive exists before about 2004, so the earliest years are built from the Statements of Changes without an independent archive cross-check. They are dated and attributed, and tagged accordingly, but not shown as Confirmed.

Reporting a problem

Every page has a "Give feedback" button at the bottom right. It captures the exact appendix and date you were viewing along with your note and goes straight to Colin's desktop. A few words is enough — a screenshot or paragraph ID makes the fix faster.

What's logged

Soft sign-in: your name and email, a UUID cookie, and an access log (route + status + timestamp) per request. Used for abuse handling and to learn what's getting used. Not shared, not indexed, not used for marketing. /admin/sessions visibility is restricted to the operator (Colin) via an environment-bound token. See the full data and privacy notice.