What the form does
Appendix B section 2.1 allows a party to an assessment of costs or expenses to serve another party with an offer to settle the amount of the bill of costs or list of expenses in Form F99.1.
Why the offer matters
After the assessment, the offer may be shown to the registrar. If the registrar decides it should have been accepted, the Rules allow consequences tied to the tariff items relating to the assessment, including potential doubling, disallowance or set-off depending on who made the offer.
Different from Rule 11-1 offers
Rule 11-1 deals with offers to settle issues in the family law case and can affect costs. F99.1 is narrower: it is specifically an offer about the amount of costs or expenses at the assessment stage.
Keep timing and proof of service
Because the consequence depends on a served offer, keep a clear record of the offer, when and how it was served, and the bill or list it was intended to resolve.
Related guides
Form F71 bill of costs · Form F55 appointment · Offers to settle.