<Li> The Netherlands and Portugal both use three groups of two characters ( letters or numbers ) in several sequences : AB - 12 - CD , 12 - 34 - AB , 12 - AB - 34 , AB - 12 - 34 , etc . However , Portuguese plates have a white background , while those of Netherlands ( after 1978 - 01 - 01 ) have a yellow one , though both countries also use white letters on blue plates for classic cars . Furthermore , newer plates on Dutch vehicles only contain consonants , to avoid coincidental abbreviations or words . Also some sensitive letter combinations , such as SS or SD , are not used . The combination ' AA ' is reserved for cars of the royal family . Dutch company registered bus , truck and / or minivan plates always start with a B or a V. Dutch taxis use blue registration plates . The number of new combinations ran out in 2008 . By now , new registered cars in the Netherlands use the following format of two digits - three letters - one digit ( 12 - ABC - 3 ) . </Li>
what does aa on a license plate mean
reserved for cars of the royal family