Technically, there is no dress code for the tribunal (it is, of course, vital you wear something). Unlike many civil courts, you will not see advocates in wig, gown and bands.
Nevertheless, hearings are formal events and it is sensible for both claimants and representatives to dress accordingly. This has two advantages. Firstly, while no tribunal is going to decide against a claimant because he’s wearing a t-shirt or because his advisor isn’t wearing a tie, hearings are about how the parties come across. Human nature being what it is, dress will be a part of this. It is likely to be a small part – but there is no need to give away points on a small issue. This applies equally to representatives as to parties. Secondly, since the tribunal will be wearing a suit and so, in all probability, will the respondent’s team, it may give the claimant or his representative a small boost in confidence to be similarly dressed.
Recommended dress for tribunals therefore, particularly for representatives, is suit and tie for men and equivalent clothing for women. In most cases, smart casual clothing will give much the same effect.
Anything likely to be seen as eccentric should be avoided. This includes a clerical collar, unless the Respondent is the Church; military uniform and a scarlet lined cape. ((Two of these examples are drawn from the authors’ experience))