Under CPR 47.7 detailed assessment proceedings must be commenced within three months of the date of the order for costs or other event under which the right to costs arose (see table at CPR 47.7). The receiving party commences proceedings by serving on the paying party the documents referred to in CPR 47.6(1) (see Section 10).

Permission to commence detailed assessment proceedings out of time is not required but if the receiving party has failed to commence detailed assessment proceedings within the deadline the paying party may apply for an order under CPR 47.8(1) disallowing all the costs to which the receiving party would otherwise be entitled unless the detailed assessment proceedings are commenced within such further time as the court may specify. The court may direct under CPR 47.8(2) that if proceedings are not commenced by the specified time, all or part of the costs to which the receiving party would otherwise be entitled will be disallowed.

An application for an order under Rule 47.8(1) must be made in writing, issued in the appropriate court office and served at least seven days before the hearing.

If the receiving party commences proceedings for detailed assessment late but before the paying party makes an application under CPR 47.8(1) the court may disallow all or part of the interest on costs that would otherwise be payable but must not impose any other sanction except in accordance with CPR 44.11(powers in relation to misconduct, see section 25).