The current fees required to pay in order to be admitted to membership can be found here

If you are admitted prior to 30 September in the current year, the Annual Subscription fee you pay on admission will cover the period from your admission date to 31 December of the current year only.

Applicants admitted after 1 October in the current year will be required to pay the following years admission fee and the annual subscription rate.

If you are admitted after 1 October, the Annual Subscription fee will cover the period from your admission until 31 December of the following year. You will only need to pay the admission fee once.

Once you have joined, your ICAS membership must be renewed annually by 1 January each year.