For any motorist or car enthusiast in the UK, understanding when and how number plates change can help you stay compliant, make informed decisions about your vehicle purchase, or even maintain the value of your car. The DVLA’s number plate update system is one of those traditions that every driver should be familiar with—whether you’re purchasing a new car, considering a personalized plate, or navigating a vehicle registration transfer.

How Have UK Number Plate Systems Changed? A Brief History

Today’s number plate system was introduced in September 2001, replacing earlier systems that used prefix or suffix letters to indicate a car’s year of registration. From 1983 to August 2001, plates began with a letter (the “prefix”) corresponding to the registration year, such as “A” for 1983–84 and “M” for 1994–95. Before that, the age identifier was at the end of the plate (the ‘suffix’). Before 1963, various regional and chronological codes were used, making it more challenging to identify a vehicle’s age or origin at a glance. 

The current system is much simpler, making the year and region quickly recognizable to both motorists and law enforcement.

How Are Number Plates Structured? Detailed Breakdown

Modern UK number plates have a distinct format: AB25 XYZ

• Local Memory Tag (First two letters): These indicate where the vehicle was first registered. For example, “LA” designates London, “MY” represents Merseyside, and “CA” is for Cymru (Wales).
• Age Identifier (Next two numbers): These identify the registration period. In March, this matches the current year (“25” for 2025). In September, 50 is added to the year (“75” for 2025). This section immediately indicates when a car was registered.
• Random Letters (Last three letters): These are randomly generated to ensure the uniqueness of each registration and generally have no meaning. They’re allocated as plates are issued and help differentiate vehicles registered in the same place and year.

Example: 

A plate such as “LA25 CVS” is a car registered in London (“LA”) between March and August 2025 (“25”), with “CVS” being a random designation.

Where Was My Car Registered? 

Here’s a quick reference for memory tag examples:

• AA–AY: Anglia
• BA–BY: Birmingham
• CA–CY: Wales
• DA–DY: Deeside to Shrewsbury
• LA–LY: London
• MA–MY: Manchester & Merseyside
• SA–SY: Scotland
• YA–YB: Yorkshire

…and many more. For a complete list, consult DVLA resources.

When Do UK Number Plates Change?

Each year, there are two official times when number plates change in the UK:

• 1st March: The first update of the year uses the year’s digits (e.g., ’25’ for 2025).
• 1st September: The second update adds 50 to the year digits (resulting in ’75’ for 2025).

This biannual system provides a straightforward method for determining a car’s age and has been in place since 2001. The changeover often sparks a surge in new car sales, as buyers seek the prestige and value associated with the latest registration.

Future Plate Sequences

Looking ahead, here are the plate identifiers you’ll see:

These patterns will continue under current DVLA rules, making it easy to spot a vehicle’s registration period for years to come.

Why the DVLA Changes Number Plates Twice Annually

The biannual update is all about clarity and fairness. Here’s a quick look at the reasons behind the DVLA’s change to the number plate system:

• Simple Age Identification: Instantly gauge a car’s age for insurance, value, and deals.
• Stability for the Motor Trade: Manufacturers and dealerships often offer attractive deals around plate change dates.
• Regulatory Transparency: Ensures straightforward, standardised compliance for everyone.

This approach streamlines everything from buying and selling to record-keeping and law enforcement.

Rules & Legalities: What Makes a UK Number Plate Road-Legal?

Whether you’re buying new, changing, or personalizing your number plates, UK law (via the DVLA) lays out strict rules for size, font, color, and spacing. Key points include:

• Front plate background: white
• Rear plate background: yellow
• Charles Wright font, 79mm tall, 50mm wide letters (except 1 & I)
• Correct spacing and margins as per DVLA standards
• No background patterns or unauthorised changes

Failing to comply can result in fines or the confiscation of your license plate. Approved suppliers must check identity and vehicle documentation before issuing road-legal plates.

Green Number Plates: What Are They & Who Can Have Them?

Introduced in late 2020, green number plates identify zero-emission (electric/hydrogen) vehicles using a green flash on the left side. 

• Purpose: Make eco-friendly cars stand out, potentially unlocking future perks in low-emission zones or with incentives, though these perks are limited at present.
• Who qualifies? Only fully zero-emission vehicles.
• Cost: Retrofitting a green plate to an eligible EV costs about £40.
• Legality: It’s illegal to fit a green plate to non-eligible vehicles.

Always buy from a DVLA-registered supplier to ensure your green plate is compliant and legal.

Buying New Plates: Tips & Cost-Saving Opportunities

• Timing Your Purchase: Buying just before or after a plate change can mean better deals on vehicles with the previous registration, as dealers clear out older stock.
• Compare Prices: Not all plate suppliers charge the same—compare costs and services to find the best value.
• Online Plate Makers: Utilize a reputable online number plate builder to customize your design, verify legal options, and often save money compared to local shops.
• Bring the Right Documents: Always take photo ID and proof of ownership when buying plates in person.

Can You Change Number Plates Back to Their Original Configuration?

It is possible to change the number plates back to the original if you’re selling a vehicle or removing a private plate. The DVLA’s process allows you to reassign the original registration (as long as it is available), restoring the car to its initial status. Early application is recommended to avoid any hitches, particularly if you’re coordinating a sale or transfer.

Staying informed about when number plates change cycles ensures your vehicle is always road-legal and attractive in the marketplace. With the correct information and resources, changing or checking your vehicle registration number is quick and hassle-free. For genuine plates, compliance tips, or guidance on your next registration update, use a trusted UK supplier or discover how to order number plates online with ease.