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HMRC internal manual

Residence, Domicile and Remittance Basis Manual

Domicile: Categories of domicile: Domicile of dependence - Adults with insufficient legal capacity

An individual who has reached the age of legal capacity (refer to RDRM22020) but who lacks sufficient mental capacity will not be regarded as having full legal capacity. They will not be able to acquire a domicile of choice, but will retain the domicile that existed on the date the incapacity began.

A parent or natural guardian can change the domicile of an incapacitated individual who became so below the age of legal capacity.