Free Reg Check: What You Can Find from a Number Plate

A vehicle’s registration number is the key to unlocking a wealth of information about its history, condition and legal status. In the UK, official government data from the DVSA (Driver and Vehicle Standards Agency) and DVLA (Driver and Vehicle Licensing Agency) is publicly available, meaning anyone can run a free reg check to learn about a car before buying it, insuring it, or simply satisfying curiosity.

This guide explains exactly what information is available, where it comes from, what its limitations are, and how to use it effectively when assessing a used car.

What a Free Reg Check Shows You

When you enter a UK registration number into a free vehicle checker, you typically get the following data points:

Vehicle Details (from DVLA)

• Make and model: The manufacturer and model name (e.g. Ford Fiesta, BMW 3 Series).
• Year of manufacture: The year the vehicle was built.
• First registration date: When the vehicle was first registered in the UK — this may differ from the manufacture date, especially for imports or pre-registered stock.
• Colour: The recorded body colour. Note that colour changes should be reported to the DVLA.
• Engine size and fuel type: Cubic capacity and whether the vehicle runs on petrol, diesel, electric or hybrid power.
• CO2 emissions: The official emissions figure, which determines the vehicle’s tax band.
• Tax status: Whether the vehicle is currently taxed, when the tax expires, or whether a SORN is in place.

MOT History (from DVSA)

• Every test result: Pass or fail for each MOT since 2005 (when digital records began).
• Defect details: All items recorded at each test, categorised as dangerous, major, minor or advisory.
• Mileage at each test: The odometer reading recorded by the testing station, creating a mileage trail you can use to spot clocking.
• MOT expiry date: When the current MOT certificate runs out.
• Testing station: The name and location of the garage that conducted each test.

What a Free Reg Check Does NOT Show

Free checks have real limitations. The following information is not available through free public services:

How to Read an MOT History

The MOT history is the most information-dense part of a reg check. Here is how to read it like a professional:

Look at the Overall Pass Rate

A vehicle that has passed most of its MOTs with minimal defects has generally been well maintained. Repeated failures — especially for the same issues — suggest neglect or a fundamental problem with the car.

Track the Mileage Trajectory

Plot the mileage figures mentally or use our checker which does it automatically. The readings should increase steadily. Any drop indicates a possible odometer reset or clocking. Large gaps between readings (more than expected for the time period) could mean the car was covering very high mileage before being wound back.

Pay Attention to Advisories

Advisory items are not failures, but they are advance warnings. An advisory for “brake disc worn but not beyond the limit” at one test often becomes a failure the next year if not addressed. Advisories that persist across multiple years suggest the owner has been ignoring maintenance recommendations.

Check for Corrosion

Structural corrosion is one of the most expensive problems to fix and often signals the beginning of the end for a vehicle. If MOT records show corrosion advisories that progress to failures, the car is deteriorating and repair costs may escalate quickly.

Understanding the UK Registration Number System

The current UK number plate format (used since 2001) follows the pattern: AA00 AAA

• First two letters: The regional identifier — indicates where the car was first registered (e.g. LA-LY = London, BA-BY = Birmingham).
• Two numbers: The age identifier — tells you the six-month period when the car was registered. Numbers 00-49 are for March registrations; add 50 for September registrations (e.g. 24 = March 2024, 74 = September 2024).
• Last three letters: Random letters to make each plate unique.

Older plates use different formats (prefix like M123 ABC, or suffix like ABC 123M) and cannot be decoded the same way. For these, the best approach is to check the DVLA data directly for the first registration date.

When Should You Run a Reg Check?

A reg check should be the very first thing you do when considering a used car — ideally before even viewing it. This saves you time and travel if the data reveals immediate problems such as:

• An expired MOT or no valid MOT at all
• A history of serious MOT failures
• Mileage inconsistencies suggesting clocking
• Vehicle details that do not match the seller’s description
• A colour change that was not mentioned in the advert

Frequently Asked Questions