If we take the plate AT65 TDR as an example:

1. The first two letters represent the ‘local memory tag’, which is where the vehicle was registered. Each place has a selection of letters to identify it.
For example, LA to LY cover London.

2. The third and fourth digits are numbers known as the ‘age identifier’. These are changed every six months in March and September. The easiest way to remember this is to think of March as the year, and September as the year plus 50. For example:

• '15' was introduced in March 2015 and '65' in September 2015
• '16' in March 2016 and '66' in September 2016
• '17' in March 2017 and '67' in September 2017
• '18' in March 2018 and '68' in September 2018
• '19' in March 2019 and '69' in September 2019

In other words, if a car has a '17' plate, it was registered between the beginning of March and the end of August in 2017, and a '67'-plate car was registered between September 2017 and the end of February 2018.

3. The last three letters are randomly chosen and allocated to a dealership when the car is registered. However, bear in mind some personalised plates don’t follow this system.

If you want to buy a new car with the latest number plate, when you visit the dealer, arrange to wait until March or September for your new car to be registered and delivered to you.

If you’re looking for a bargain, however, it can work out best to buy sooner. Dealers sometimes get rid of old stock at discounted prices in February and August each year.

If you're wondering when the best time to buy a car is, we've got more information.

In the old format, number plates followed this style: A 470 TDR

1. The first letter is the ‘age identifier’, representing the year the car was registered. This originally changed each year in August, but from 1999 it was updated every six months instead.

2. The three digits are random numbers.

3. Two of the final three letters indicate the area of registration, while the other is random.
From 1963 to 1983, the letter identifying the year of the car was at the end of the plate, and the original once-a-year plate change system operated until 1999. As a result, dealers would see a huge increase in car sales in August each year from drivers who wanted to be seen in the newest cars, which led to lower sales during the rest of the year.

This system was phased out in 2001 and changed to the twice-yearly one, which is still in place today.

The DVLA says the format will be reviewed and updated again in 2050, so you've got a while before you have to worry about that.

Here’s the full list of number plate years and their age identifier for used cars:

• 1963 A
• 1964 B
• 1965 C
• 1966 D
• 1967 E/F
• 1968 F/G
• 1969 G/H
• 1970 H/J
• 1971 J/K
• 1972 K/L
• 1973 L/M
• 1974 M/N
• 1975 N/P
• 1976 P/R
• 1977 R/S
• 1978 S/T
• 1979 T/V
• 1980 V/W
• 1981 W/X
• 1982 X/Y
• 1983 Y/A
• 1984 A/B
• 1985 B/C
• 1986 C/D
• 1987 D/E
• 1988 E/F
• 1989 F/G
• 1990 G/H
• 1991 H/J
• 1992 J/K
• 1993 K/L
• 1994 L/M
• 1995 M/N
• 1996 N/P
• 1997 P/R
• 1998 R/S
• 1999 S/T/V
• 2000 V/W/X
• 2001 X/Y/51
• 2002 02/52
• 2003 03/53
• 2004 04/54
• 2005 05/55
• 2006 06/56
• 2007 07/57
• 2008 08/58
• 2009 09/59
• 2010 10/60
• 2011 11/61
• 2012 12/62
• 2013 13/63
• 2014 14/64
• 2015 15/65
• 2016 16/66
• 2017 17/67
• 2018 18/68
• 2019 19/69

If you're looking to buy a new car in 2019, the 19-plate will be released on 1 March 2019. It will apply to any new vehicle registered from 1 March until 31 August 2019.

From 1 September 2019, the number plate will change to a 69-plate, and will apply to all new vehicles registered until February 29 2020.