Table of Contents

  • What is a VIN or Chassis Number?
  • Difference between a VIN Number, a Chassis Number and an Engine Number?
  • History of the VIN Number
  • What do the numbers and letters in a VIN mean?
  • Where can I find the VIN or Chassis Number?
  • Why should you check your vehicle identification number?
  • What if the VIN is not 17 characters long?
  • What should you do if the VIN Number on the car is different from the log book?

What is a VIN or Chassis Number?

Cars have had serial numbers since the early days of the motor industry, but there wasn’t a standard until VIN numbers were ratified in the early 1980s.

To sum it up, a VIN number – also called Vehicle Identification Number – is your car’s unique identity code. It comes in the shape of a 17-digit number stamped into the chassis of every car on the planet. That is why it can also be called Chassis Number. They display the car’s unique features, specifications and manufacturer.

VIN Numbers are unique to each car and cannot be changed. They’re given to the vehicle on the production line and are fixed to that car forever. This also means that there are no cars with the same VIN. And also makes them a vital tool to prove a car’s identity and authenticate ownership.

Vehicle Identification Numbers can be used to track recalls, registrations, warranty claims, insurance coverage or thefts.

Difference between a VIN number, a Chassis Number and an engine number?

Vehicle Identification Numbers (VIN) and Chassis Numbers are the same. The two are interchangeable and mean the same.

Car engine numbers are, however, another thing. They are not fixed to the car and, like other components, can be changed. But because the engine is such a vital part of a car they are also given a number to specify size and power output.

Car engine numbers are useful when you need to replace your engine for a new one. Then the car will be assigned a new engine number. The VIN Number will stay the same.

History of the VIN Number

Vehicle Identification Numbers as we know them today were ratified in 1980 by the International Organisation for Standardisation (ISO) as the standard. It’s a global system of 17-digit chassis numbers that is applied to every single vehicle produced worldwide.

Before that, each individual carmaker had their own method of recording vehicle and component identities. The lack of a standard meant it was easy for crooks and fraudsters to create fake IDs and ownership documents for cars.

What do the numbers and letters in a VIN mean?

Any car from 1981 to the present day will have 17 character VIN Numbers. Cars pre-1981 may have shorter identification numbers.

VIN numbers can include any digit from 0 to 9 and any letter of the alphabet except for I, O and Q because they could be confused with numbers.

Understanding all the components on the VIN number can feel like a challenge because they are long and very specialised but we’re going to break down the basics for you. These are the three main components.

Digits 1 to 3 – World Manufacturer Identifier (WMI)

The first three characters of the VIN Number are the World Manufacturer Identifier section. They identify the manufacturer of a motor vehicle or trailer.

The first character is for the country where the manufacturer or the company’s HQ is located. The second and third characters are assigned to different companies. For example, all UK manufacturer VIN numbers start with S. For example SAJ stands for Jaguar, SBM for McLaren or SAL for Land Rover.

Digits 4 to 9 – Vehicle Descriptor Section (VDS)

This is the part of the VIN Number that describes the general attributes of the vehicle – type of vehicle, platform, body style, engine option, etc.

If the manufacturer doesn’t use one or more of these spaces, they will be filled by letters or numbers that the car maker will choose.

Digits 10 to 17 – Vehicle Identifier Section (VIS)

The last section of the VIN Number has eight characters and the last four should be always numbers. These last digits identify a specific vehicle and are usually the car’s serial number, although they may include information on options or powertrain choices.

Photo by Andras Vas on Unsplash

Where can I find the VIN or chassis number?

Vehicle Identification Numbers can be found stamped in several parts of your car and they should always match. Remember, there is only one VIN Number per vehicle.

On a modern car the easiest place to spot your chassis number is at the base of the windscreen on the passenger side. It’s called ‘Visible VIN‘ and is easy to spot.

For extra security when you’re doing a car check, it’s good to look for the VIN Number in other areas of the car. Depending on the age of the vehicle, it could be on a metal plate attached to the chassis or bodywork, or directly stamped into the metalwork. Some manufacturers, for example, like adding the Vehicle Identification Number to the door post – where the door latches when it’s closed. In other cases the VIN Number will be under the bonnet or behind plastic trim or carpets around the front doors of the car. Usually handbooks reveal the location of these marks, but if you don’t have it checking in these places should do the trick.

VIN Numbers are also featured on the car registration document. Just look in the Vehicle Details box at the top of page 2 on a car’s V5C doc and there’s a field marked ‘VIN/Chassis/Frame No.’ Below you’ll see the car’s engine number.

Why should you check your vehicle identification number?

You should always check the VIN Number when buying a used car. That means checking the printed chassis number on the V5 vehicle registration document matches the actual number stamped on the car – in all its locations. If they don’t, that could mean the car was stolen and you should walk away.

Car manufacturers also use the Vehicle Identification Number to issue car recalls. So it may be handy to know it just in case your vehicle gets recalled for some reason.

What if the VIN is not 17 characters long?

Unless you’re checking the VIN of a classic car produced before 1981, all car’s vehicle identification numbers should have 17 alphanumeric characters. If the car is post-1981 and doesn’t have them it cannot be correct.

First and foremost, make sure you’ve copied the number correctly. Count the numbers and make sure you’ve not missed any. If you’ve not missed any numbers and the VIN is not 17 characters long, then there may be something wrong with it if the car was manufactured after 1981.

What should you do if the VIN number on the car is different from the log book?

All VIN numbers on a car need to be identical and match. If they’re different all your alarms should bells should ring. Same applies to the Chassis Number being different to the one from the log book. In both cases, don’t buy the car. Walk away and notify the police once you’re at a safe distance and in a secure place.

When the VIN numbers in a car are different that could mean that you’re looking at a ‘cut and shut’ car. That is a car made from the parts of other vehicles. Or a ‘clone’. This is where criminals will take the VIN number from one car and transfer it to another that was stolen in an attempt to hide the origin of the vehicle. They will usually have forged paperwork to help them mask the crime.

VIN Number’s are designed to be foolproof and clear. If there are any inconsistencies, don’t trust the seller. And make sure you read our car scams guide for more information.