Beta This part of GOV.UK is being rebuilt – find out what this means

HMRC internal manual

Tax Credits Technical Manual

From
HM Revenue & Customs
Updated
, see all updates

Decision Making, Joint or Single claims: Prohibited relationships

Marriage Act 1949, Marriage (Scotland) Act 1977 & Marriage (Prohibited Degrees of Relationship) Act 1986

Throughout the United Kingdom (UK) the law prohibits certain blood relatives, step relatives and relatives-in-law from getting married or becoming civil partners. For example a woman cannot marry her grandfather or uncle and a man cannot marry his daughter or sister. Please see below for a list of prohibited relationships. The legislation is slightly different in Scotland to that of the rest of the UK but in general the same provisions apply.

Where it is established that a claimant is living with a relative who appears on the list of prohibited relationships they cannot be regarded as living together as a married couple (LTAMC) or civil partners (LTACP). This is because they cannot marry or form civil partnerships in law so they cannot be said to be LTAMC or LTACP. The claimant will therefore be treated as a single claimant.

List of prohibited relationships for marriage and civil partnerships

Throughout the United Kingdom (UK), Guernsey, Jersey and the Isle of Man, the law prohibits certain blood relatives, step relatives and relatives-in-law from getting married or registering as civil partners. Unless they fall within the exception below a person cannot marry or become civil partners with their:

  1. child
  2. adoptive or former adoptive child
  3. child of former spouse or civil partner
  4. parent
  5. adoptive or former adoptive parent
  6. former spouse or civil partner of parent
  7. parent’s sibling
  8. sibling or sibling’s child
  9. grandparent
  10. former spouse or civil partner of grandparent
  11. grandchild
  12. grandchild of former spouse or civil partner

In the above list “sibling” means a brother, sister, half-brother or half-sister.

For the people mentioned in 1, 2, 4, 5, 7, 8, 9 and 11, the bar to marriage or registering as civil partners of each other is absolute.

Exceptions

For the people mentioned in 3, 6, 10 and 12, there are some exceptions. They can marry if both parties are over 16 years of age, or register as civil partners if both parties are over 21 years of age, and the younger person was never a child in the older person’s family before they reached age 18.

“Child of the family”, in relation to another person, means a person who

  1. has lived in the same household as that other person and
  2. has been treated by that other person as a child of their family

Additionally, if either person is under 21, and/or they are in an ‘in-law’ relationship with the other person they cannot marry or form a civil partnership, where any person originally involved in creating the ‘in-law’ relationship is still alive. For example we do not consider LTACP if a woman lives in the same household as her daughter-in-law and the woman’s son or husband is still alive.