Construction Industry Scheme returns for the period from 6 December 2016 to 5 January 2017 should be submitted online by 19 January. This includes NIL returns.
It is too easy to forget the need to submit a NIL return when no payments to subcontractors have been made. If you engage a firm of local accountants to do your CIS returns, then this will be taken care of. In our case we keep a diary and do a batch of work at about the same time each month.