Sources, decisions and limitations
How V55/5 guidance works
The service combines official-source guidance with a tested registration-route engine. This page explains how an answer becomes a recommendation and where human confirmation remains necessary.
Source hierarchy
We prefer current GOV.UK guidance and official DVLA, HMRC and DVSA forms, manuals and notices. Help answers link to the sources supporting the practical instruction.
Deterministic route rules
NOVA, approval, MOT, Q-plate risk, payment and enclosure decisions are calculated from explicit answers. Missing facts produce provisional guidance rather than invented certainty.
Document reading
Optional vehicle documents are processed transiently. Extracted values are presented for review, low-confidence or conflicting values are not silently accepted, and identity documents are rejected.
Review and updates
Rules and high-value answers carry review dates. Automated freshness checks flag changed government sources, while material rule changes require code and test updates before publication.
What the service cannot verify
We cannot see HMRC or DVLA records, inspect the vehicle, authenticate an uploaded document or guarantee that DVLA will accept a particular evidence bundle. The registration route distinguishes user answers, derived rules and recorded milestones so those limits remain visible.
Found an outdated rule or unclear answer?
Send the page and supporting official source for review.