UK number plates explained
On a current-style UK plate the two digits in the middle give the registration period: 26 means March 2026 to August 2026 and 76 means September 2026 to February 2027. So the plate dates the car to a six-month window — but it does not prove the car’s age, because a private registration can be transferred onto an older car.
The one rule that never bends: a registration can make a car look older than it is, never newer. DVLA states it flatly in INF104: you cannot use a registration number to make a vehicle appear younger than it actually is. INF104 attaches no fine to that rule — what it says is that if you misrepresent a registration number you do not get back any money you have paid for it. So a plate suggesting a car is younger than it is cannot legitimately exist, while a plate suggesting it is older is routine.
The format: two letters, two digits, three letters
A current-style UK registration is seven characters in three parts, and only the middle part carries a date.
Memory tag
Two letters. The first identifies the DVLA local memory office area in which the registration was issued; the second narrows it to an office within that area.
Age identifier
Two digits. They name the six-month period in which the registration was issued. This is the only part of the plate that carries a date.
Random letters
Three letters whose only job is to make the registration unique. They say nothing about the car, the keeper or the area.
This format was introduced in September 2001 (DVLA INF104). Older cars carry the earlier styles — a single-letter prefix before the numbers, and before that a suffix letter after them — which encode age differently, and a transferred private registration may follow no age pattern at all.
The age identifier, and the rule that generates it
Two changes a year, in March and September. A March registration takes the last two digits of the year. A September registration takes the same two digits plus 50. That is the whole rule, and it produces the identifiers on the road now and next:
| Age identifier | Issued | Registration period |
|---|---|---|
| 26 | March issue | March 2026 to August 2026 |
| 76 | September issue | September 2026 to February 2027 |
| 27 | March issue | March 2027 to August 2027 |
| 77 | September issue | September 2027 to February 2028 |
The rule works backwards just as well, which is how you read any plate on a forecourt. 02 is March to August 2002; 52 is September 2002 to February 2003; 17 is March to August 2017; 67 is September 2017 to February 2018.
The part most often got wrong: January and February do not start a new identifier. They still carry the previous September’s. A car first registered in January 2026 wears a 75 plate — the identifier issued from September 2025 — not a 26 one. The mistake runs both ways: a 75 plate reads as a 2025 car, and it may in fact have been first registered in January or February of the year after that.
Two more things follow from the six-month cycle. First, an identifier covers a range, not a month: a 26 car could have been registered on any day from March 2026 to August 2026, and the difference between the two ends of that range is nearly half a year of use. Second, the plate is not a model year. A manufacturer’s model year and a UK registration period are separate things and do not have to line up.
What the memory tag indicates, and what it does not
The two opening letters record the DVLA local memory office area in which the registration was first issued. That is a fact about the registration, at the moment it was issued, and it is the only thing the tag establishes.
What it indicates
- The DVLA local memory office area where the registration was issued.
- A narrower office within that area, from the second letter.
- Nothing that changes afterwards — it is fixed at issue.
What it does not prove
- Where the car was built, or by whom.
- Where the car has been kept, driven or serviced.
- Where the current keeper lives, or where any previous keeper lived.
- Anything at all, if the registration has been transferred: the tag then describes the origin of a registration, not of this car.
A car does not get a new tag when it moves. A registration issued in one office area stays on the vehicle through every subsequent keeper and every subsequent address, so “it is a local car” is not something a plate can tell you. Where a car has actually spent its life shows up in the MOT history — the test locations and the recorded mileage — not in the first two letters.
Private and personal registrations break the link entirely
A registration can be transferred from one vehicle to another, and a retained registration can be held and reassigned later. This is ordinary and lawful, and it means the plate on a car may have no relationship to that car’s history.
- The age identifier may be older than the car. An older registration on a newer car is allowed, so a plate can understate the age by years.
- There may be no age identifier at all. Many private registrations use older formats, or formats that were never dated, so nothing on the plate encodes a period.
- The memory tag becomes meaningless. It describes where that registration was issued, on whatever vehicle first carried it.
- The plate can change before you take delivery. If a seller is removing a private registration, the car you collect will not be wearing the registration in the advert. Ask before, not after.
The practical consequence is that the plate is a starting point and never the evidence. The date of first registration on the V5C is the field that settles a car’s age, and the MOT history is the independent record that corroborates it.
You cannot make a car look newer than it is
The transfer rules run one way only. An older registration may go on a newer vehicle; a newer registration may not go on an older one.
The penalties printed alongside that rule in INF104 belong to a different offence. The consequence INF104 names for misrepresenting a registration number is financial: you do not get back any money you have paid for the number, or any other costs you have to pay. The fine of up to £1,000, the failed MOT and the permanent withdrawal of a registration that appear on the same page are stated for driving with incorrectly displayed number plates — rearranged or altered letters and numbers — and INF104 qualifies withdrawal with “in some cases”. Either way, the asymmetry is what makes plate-reading safe in one direction: if a plate suggests a car is older than the seller says, treat the plate as the more likely truth and check the V5C. If it suggests the car is newer, something is wrong.
Why the registration date decides the running cost
The date of first registration, which the age identifier points at, decides which vehicle tax system a car sits in for the rest of its life. Three dates do the work: 1 March 2001, 1 April 2017 and 1 April 2025. Used stock is spread across all of these boundaries rather than sitting neatly on one side.
Engine size only
CO2 is not used. £230 a year up to 1549cc, £375 above it.
A CO2 band for life
The same graduated rate every year, £20 to £790. No first-year charge and no Expensive Car Supplement.
Flat standard rate
A one-off CO2-based first-year rate, then £200 every year after. A used buyer pays the standard rate.
Two of those dates fall inside a plate period, not at the start of one
The plate changes in March and September. The tax boundaries fall in April. So a single age identifier can cover cars on either side of a cliff, and the plate cannot tell you which side a given car is on.
- 17 plate, 1 April 2017. A 130 g/km petrol car registered in March 2017 sits in Band D at £170 a year for life. The identical car registered that April pays the flat £200 standard rate. Same plate, different system, every year for as long as the car exists (2026/27 rates).
- 1 April 2025, for zero-emission cars. A zero-emission car first registered between 1 April 2017 and 31 March 2025 pays £200 and no Expensive Car Supplement at any list price. One first registered on or after 1 April 2025 can be caught by the supplement on a £50,000 list-price threshold that takes effect on 1 April 2026 — £640 a year on a car that listed at £60,000 when new, in years 2 to 6.
The Expensive Car Supplement is £440 a year in years 2 to 6, assessed on the list price when the car was new rather than what you pay for it second hand. A used advert therefore cannot answer it at all: the V5C or the seller can. To put a specific registration date, CO2 figure and original list price through the right system, use the car tax calculator, and see vehicle tax when you buy a used car for what happens to the tax at the moment of sale.
The 2001–2017 bands, for the cars a plate most often dates
Paid every year, unchanged for the life of the car. 2026/27 rates.
| Band | CO2 (g/km) | Per year |
|---|---|---|
| A | 0–100 | £20 |
| B | 101–110 | £20 |
| C | 111–120 | £35 |
| D | 121–130 | £170 |
| E | 131–140 | £200 |
| F | 141–150 | £225 |
| G | 151–165 | £275 |
| H | 166–175 | £325 |
| I | 176–185 | £360 |
| J | 186–200 | £410 |
| K | 201–225 | £445 |
| L | 226–255 | £760 |
| M | Over 255 | £790 |
How to check a car really is the age its plate suggests
- Read the date of first registration on the V5C. That field, not the plate, is the car’s age. Check it in person, on the document, not from a photo of the front of the car.
- Put the registration through the DVLA vehicle enquiry service on GOV.UK. It returns the month and year of first registration from the registration alone, so it either agrees with the V5C or it does not.
- Open the MOT history. Testing starts at three years old in Great Britain and at four in Northern Ireland, so the earliest test on record brackets the registration date independently of anything the seller says. Our MOT check tool works out when the next test is due from that date.
- Ask directly whether the registration has ever been changed. A transferred or retained registration is normal, but it means the plate is not evidence of age and the V5C is doing all the work.
- Ask what it listed at when new if it is a 2017-or-later car. The Expensive Car Supplement turns on that figure and no advert carries it.
- Check the age boundaries that matter for the car in front of you. A vehicle old enough to be near the historic exemptions is a separate question — see is my car exempt from the MOT, because the tax exemption and the testing exemption are different rules with different tests and different dates.
Great Britain and Northern Ireland
Registration and vehicle tax are DVLA matters across the whole UK, so the transfer rules and the three tax systems above apply everywhere. INF104 itself is DVLA guidance that makes no mention of Northern Ireland, so read its number-plate display detail as stated for Great Britain. Two further things do not carry across.
- The age identifier itself. Registrations issued in Northern Ireland use a separate, undated format, so the two-digit identifier described here does not appear on them and such a registration says nothing about the year of registration.
- The MOT cross-check. Testing in Great Britain is run by DVSA with the first test on the third anniversary of registration; in Northern Ireland it is run by DVA with the first test at four years old. Public MOT history goes back to 2005 in England, Scotland and Wales but only to 2017 in Northern Ireland, so an older car bought there has a shorter documented trail.
Where these figures come from
- Plate format, memory tags, age identifiers and the age rule on transfers: DVLA INF104, vehicle registration numbers and number plates. gov.uk INF104. Every identifier printed on this page is generated by the same module the site’s plate decoder uses, so the two cannot disagree.
- Vehicle tax rates: GOV.UK vehicle tax rate tables, 2026/27, verified 2026-07-28. gov.uk/vehicle-tax-rate-tables.
- First-test ages and MOT history depth: DVSA for Great Britain, DVA for Northern Ireland.
This page explains how registrations are structured. It is not advice on a specific vehicle: for the age of a particular car, read the V5C and the DVLA vehicle enquiry service.