Ties on hats are legal. There is a British Standard  on the different requirements for cords, ties, drawstrings and loops and it is dependent on the age of the child as well as the area it is placed on the garment. However items that are exempt are:

•    Gloves, hats, bonnets and scarves

•    Bibs and nappies

•    Shoes and boots 

•    Belts and braces

•    Aprons

Although items such as hats, or mittens with strings do NOT need to comply to these rules we always assess how long any cords or ties are to minimise risk.  However, it is parental choice as to what works for them and we always try to offer a variety - for example hats with no ties, hats with Velcro™ tabs, hats with ties.  For some people the only hat that will stay on is one with ties.  With mittens we offer some on strings and some not.