Decode VIN Assembly Plant Codes
The Short Answer
On vehicles built for the US market since the 1981 model year, the assembly plant code is the 11th character of the 17-character Vehicle Identification Number (VIN). It is a single letter or digit that identifies the factory where the vehicle was assembled.
There is an important qualification. Each manufacturer assigns its own plant codes, so the 11th character means nothing by itself. A given letter can point to one factory for one brand and a completely different factory for another. To decode it correctly, you need the manufacturer, which comes from the first three characters, and often the model year, which comes from the 10th character, because manufacturers can reassign codes over time.
Where the Plant Code Sits in a VIN
US federal VIN rules (49 CFR Part 565) define a fixed 17-character structure for vehicles sold in the United States. The plant code makes sense only in the context of the characters around it.
Position(s) | Section | What it identifies; 1–3 | World Manufacturer Identifier (WMI) | Manufacturer and, through the first character, the region or country of origin; 4–8 | Vehicle Descriptor Section | Vehicle attributes such as model, body style, restraint system or engine, using manufacturer-defined codes; 9 | Check digit | A calculated value used to detect transcription errors or invalid VINs; 10 | Model year | The vehicle's model year, encoded as a letter or digit; 11 | Assembly plant | The manufacturer-assigned code for the factory where the vehicle was assembled; 12–17 | Production sequence | The vehicle's serial number
VINs never use the letters I, O or Q, because they are too easily confused with 1 and 0. If you think you see one of these letters in position 11, you have most likely misread a digit.
How to Decode the Plant Code Step by Step
1) Read the full 17-character VIN from at least two places, such as the base of the windshield on the driver's side and the label on the driver's door jamb, and confirm that they match. 2) Identify the manufacturer from the first three characters (the WMI). 3) Note the model year from the 10th character. 4) Read the 11th character. This is the plant code. 5) Look up that character in the manufacturer's plant code list for the relevant model year, or run the full VIN through a decoder that returns plant information, such as NHTSA's free VIN decoding tool.
Decoding the full VIN is usually more reliable than looking up the 11th character on its own. The decoder applies the manufacturer and model-year context for you, which avoids matching the letter against the wrong brand's table.
What the Plant Code Does and Does Not Tell You
The plant code identifies where the vehicle was assembled. It does not necessarily tell you where the major components came from. Engines, transmissions and other parts are often built at separate facilities, sometimes in other countries. Information about parts content is reported separately from the VIN, for example on the parts-content label shown on new vehicles in the US.
The plant code also differs from the country indicated by the first VIN character. The first character reflects where the manufacturer identifier is registered. That usually matches the assembly country, but not always, so use the plant code when you specifically need the assembly location.
Limits and Exceptions
Pre-1981 vehicles: VINs before the standardized 17-character format varied in length and layout by manufacturer, so a plant code, if present, may be in a different position. Vehicles built for other markets: The international VIN standard does not require a plant code in position 11. Many manufacturers place it there anyway, but a vehicle built for another market may follow a different scheme. Code reassignment: Manufacturers can reuse or change plant codes when plants open, close or change ownership, so always check the code against the correct model year. Low-volume and specialty builders: Small manufacturers may use simplified schemes, so check their own documentation.
Gaps in This Guide
This guide does not include plant code tables for any specific manufacturer, because no confirmed brand-by-brand plant listings were available. To identify a specific factory, use a full-VIN decoder or the manufacturer's own VIN documentation for the vehicle's model year.
