UK number plate age identifier decoder.

How the age identifier and memory tag work

Since 1 September 2001 a standard UK registration number has had one layout: a two-letter memory tag, a two-digit age identifier, a space and three random letters. DVLA publishes the layout, the memory tag list and the age identifier list in its leaflet INF104, and this decoder reads a plate against those same published tables. Paste a registration such as AB25 CDE and it splits the plate into its three parts, then looks up the first two parts.

Reading the age identifier

The age identifier changes twice a year. Numbers issued from March to August carry the last two digits of that year, so March 2025 to August 2025 is 25. Numbers issued from September to the following February carry the year plus 50, so September 2025 to February 2026 is 75. The DVLA table starts at 51 for September 2001 to February 2002 and runs to 79 for September 2029 to February 2030. The document adds that the pattern continues until all possible variations have been used, so the table is a published window and not a promise that a code stops existing after it.

That second rule is where most manual decoding goes wrong. A plate with 75 is not from 2075 and not from 1975, and it is not a 2025 plate either: it could have been issued in September to December 2025 or in January or February 2026. Subtract 50 to get the starting year and remember the period runs into the next calendar year. The tool prints the exact span from the DVLA table so you do not have to do the arithmetic.

Worked example

These plates are made up for illustration, not real vehicles.

For SK75 XYZ, 75 minus 50 gives 25, so the period starts in September 2025. Because the code is in the 51 to 79 band, it ends in February of the following year. If the vehicle's first registration paperwork says January 2026, a 75 plate is exactly what you would expect.

Which memory tags exist

The tool checks the tag against the full DVLA table, which lists every office and the second letters it uses. The table below reproduces it. Note the gaps: the table has no FO, FU or NF, and DVLA says it will not use I, Q or Z in local memory tags (existing Q marks are still issued). A tag that is not in the table fails here even though it looks plausible.

Two tags are reserved. HW is used exclusively for Isle of Wight residents, and MN together with the random letters MAN is reserved for the Isle of Man. The tool prints a note when it sees either.

Edge cases and common mistakes

• Treating the identifier as the build year. It shows when the number was issued. A registration number is allocated to a vehicle when it is registered and taxed, and it stays with the vehicle unless the keeper moves it to another vehicle or a retention certificate. A moved or personalised number can look newer or older than the vehicle it is on.
• Assuming the tag is where the car lives now. The memory tag refers to the region where the vehicle was first registered, so a car sold across the country keeps its original tag.
• Confusing 02 with 2002 in both halves. Code 02 is March to August 2002. September 2002 to February 2003 is 52.
• Reading a missing letter as a typo. Because the table omits some combinations, a valid-looking tag can be one DVLA does not use for local offices.
• Using a number to make a vehicle look younger. INF104 says you cannot use a registration number to make your vehicle appear younger than it actually is.

Who this is for

Buyers checking whether a plate fits a seller's description, people reading an old log book or insurance schedule, fleet and auction admins who want to sanity-check a batch of plates, and anyone who has seen a plate and wondered what the two numbers mean.

What this does not cover

The decoder does not look up a vehicle, an MOT, tax, insurance or keeper details, and it does not tell you whether a plate has been issued. It does not decode pre-2001 plate layouts, personalised or cherished transfers that break the format, or number plates that are not issued under the DVLA scheme. It reads the shape and two tables, nothing more.

Sources

• GOV.UK: Vehicle registration numbers and number plates (INF104)
• DVLA INF104 (PDF, 4/22): format, memory tags, age identifiers

Retrieved 20 October 2026. Issuing bodies can change these rules; check the source if a result matters.

FAQ

What is the age identifier on a UK number plate?

It is the two digits after the memory tag on a plate issued since 1 September 2001. DVLA says the two numbers tell you when the number was issued: 02 to 29 mean March to August of that year, and 51 to 79 mean September to the following February, with 50 added to the year.

How do I tell what year a UK number plate is from?

Look at the two digits in the middle. If they are below 50, add them to 2000 and the plate was issued between March and August of that year (25 is March to August 2025). If they are 51 or higher, subtract 50 and the plate was issued from September of that year to February of the next (75 is September 2025 to February 2026).

What do the first two letters of a UK number plate mean?

They are the DVLA memory tag. DVLA says they refer to the region in the country where the vehicle was first registered. The first letter is the region and the second letter points to a local DVLA office, for example AB for Peterborough in the Anglia region.

When does the UK age identifier change?

Twice a year. The DVLA table switches from the March code to the September code for each year, so a vehicle registered in October 2025 carries 75 and one registered in April 2026 carries 26.

Does the age identifier prove how old the car is?

No. It shows when the registration number was issued. DVLA says the number stays with the vehicle unless the keeper moves it to another vehicle or a retention certificate, so a transferred number can be older or newer than the vehicle it is on.

Which letters are never used in a UK memory tag?

DVLA says it will not use I, Q or Z in local memory tag identifiers. Existing Q marks are still issued, and Z is used only as one of the three random letters at the end.

What happens after the 79 plates in 2029?

The DVLA table ends at 79 for September 2029 to February 2030, and the document says the pattern will continue until all possible variations have been used. This tool only decodes codes inside the published table.

Can this tool look up a vehicle, MOT or tax status?

No. It decodes the plate’s own structure in your browser and does not contact DVLA or any vehicle database.