This Practice Note deals with the circumstances where a claim is made for child support and paternity or parentage is disputed. It details the cases in which the child maintenance service (CMS) can make an assumption as to parentage, steps to take where paternity or parentage is denied and the impact on liability.

Section 26 of the Child Support Act 1991 (CSA 1991) provides that where a person who is alleged to be the parent of a child for whom a maintenance calculation has been made denies that he is one of the child’s parents, the CMS shall not make a maintenance calculation on the assumption that the alleged parent is one of the child’s parents, unless the case falls into one of the categories set out in CSA 1991, s 26(2), see: Assumption of parentage. CSA 1991 also makes provision as to a denial of parentage where assumptions do not apply and a denial of parentage where assumptions apply.

For general guidance on the statutory child support scheme, see Practice Note: Statutory child support scheme.