Answer by Alnitak for Reformat string containing uk postcode using regex

Put braces around the bits separated by the optional space:

/^([A-Za-z]{1,2}[0-9A-Za-z]{1,2})[ ]?([0-9]{0,1}[A-Za-z]{2})$/

However I think the regexp is wrong... The above regexp splits "N13LD" as "N13", "LD".

I suspect the errant part is the {0,1} before the two trailing letters - there must AFAIK be exactly one digit there:

var re = /^([A-Z]{1,2}[\dA-Z]{1,2})[ ]?(\d[A-Z]{2})$/i; // case insensitive

The grouping allows the string.match(regexp) function to return a result which includes an entry for each matching group:

> "N13LD".match(re);["N13LD", "N1", "3LD"]> "GU348RR".match(re);["GU348RR", "GU34", "8RR"]> "EC1A3AD".match(re);["EC1A3AD", "EC1A", "3AD"]

To get your result, just use trivial string concatenation to join the 2nd and 3rd element from each result together.