Detailed assessment proceedings must be commenced within three months after the judgment, order or event giving rise to the right to costs (CPR 47.7); in civil recovery proceedings under the Proceeds of Crime Act 2002 the time limit is reduced to two months.  The parties may agree between themselves to extend or shorten the time specified by the rule for commencing detailed assessment proceedings. A party may apply to the appropriate office (see 10.7 below) for an order to extend or shorten the period of three months, but permission is not required to commence detailed assessment proceedings out of time.

If the receiving party fails to commence detailed assessment proceedings within the period specified by the rule, or by order of the court, the paying party may apply for an order under CPR 47.8(1) requiring the receiving party to commence the proceedings within a specified time. The court may direct that unless the receiving party does commence the detailed assessment proceedings within the time specified by the court, all or part of the costs will be disallowed.

Where the receiving party commences proceedings for detailed assessment out of time but the paying party has not made an application under CPR 47.8(1), the court may disallow all or part of the interest otherwise payable to the receiving party but the court will not impose any other sanction unless there has been misconduct (CPR 47.8(3)).