EIM76102 | Social security benefits: dependency additions
From HM Revenue & Customs · Employment Income Manual
Sometimes a claimant can get extra benefit if he or she has a dependent.
Child dependency additions are not taxable, even if the basic benefit itself is taxable.
Where an adult dependency addition is payable the following rules apply:
if the benefit is listed at EIM76100 the adult dependency addition is not taxable
if the benefit is listed at EIM76101 the adult dependency addition is taxable.