There is no single rule.

If the couple want particular ties, pocket squares, cufflinks or other accessories to create a coordinated wedding look, paying for those items can be a thoughtful way of keeping the financial responsibility with the couple.

Alternatively, the groomsmen can contribute towards some items if everyone is comfortable with the arrangement.

The important thing is to make the costs clear before people commit, particularly if the accessories form part of a larger wedding-party expense.