An electronic bill of costs must be served in Part 7 multi-track claims where the costs claimed were incurred post 6 April 2018. There are three exceptions: cases in which the proceedings are subject to fixed costs or scale costs; cases in which the receiving party is unrepresented; or where the court has otherwise ordered.​

Where costs are claimed both pre and post 6 April 2018, the receiving party has two options. They may prepare a traditional paper bill of costs for the costs incurred pre 6 April 2018 and an electronic bill of costs for those costs incurred post 6 April 2018, or they may prepare an electronic bill of costs for all costs incurred. The latter tends to be more cost-effective and the preferred option in practice.

The time by which detailed assessment proceedings must be commenced is 3 months after the date of the judgment, order, award or other determination; 3 months after the date of service of notice of discontinuance under rule 38.3; or 3 months after the date when the right to costs arose following an acceptance of a Part 36 offer.

Where the receiving party fails to commence detailed assessment proceedings within the three month period, the paying party may apply for an order requiring the receiving party to commence detailed assessment proceedings within such time as the court may specify.

If the paying party does not make such an application in accordance with paragraph and the receiving party commences the proceedings later than the three month period, the court may disallow all or part of the interest otherwise payable. However, the court will not impose any other sanction unless there is misconduct.

Paragraph 5.2 of CPR Practice Direction 47 provides that on commencing detailed assessment proceedings, the receiving party must serve on the paying party and all the other relevant persons the following documents:

(a) a notice of commencement in Form N252;

(b) a copy (or, where paragraph 5.A4 applies, copies) of the bill of costs;

(c) copies of the fee notes of counsel and of any expert in respect of fees claimed in the bill;

(d) written evidence as to any other disbursement which is claimed and which exceeds £500;

(e) a statement giving the name and address for service of any person upon whom the receiving party intends to serve the notice of commencement;

(f) if a costs management order has been made (and if the same information is not already fully provided in an electronic bill), a breakdown of the costs claimed for each phase of the proceedings. Precedent Q in the Schedule of Costs Precedents annexed to this Practice Direction is a model form of breakdown of the costs claimed for each phase of the proceedings.

The amount of costs that will be recovered will largely depend on whether the costs are to be assessed on the standard basis or indemnity basis. On the standard basis, any doubt as to whether costs are reasonable and proportionate will be resolved in favour of the paying party. Furthermore, the court will only allow costs which are proportionate to the sums in issue, value of any non-monetary relief, complexity of the litigation, the paying party’s conduct, and any wider factors, such as reputation or public importance. On the indemnity basis, there is no such proportionality requirement, and any doubt as to whether costs are reasonable and proportionate will be resolved in favour of the receiving party.

It is widely considered that receiving parties can generally expect to recover 70 – 80% of the bill of costs, however, there are many factors that influence the level of recoverable costs.

The costs of preparing the bill of costs are claimed within the bill of costs itself and are recoverable from the paying party.