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HMRC internal manual

Trusts, Settlements and Estates Manual

Property held jointly by married couples or civil partners: The 50/50 rule: New source

There is no problem with property which neither spouse or civil partner held before they got married or registered as civil partners; for example, they buy Government stock (which pays gross interest) in their joint names after they get married or register as civil partners. The 50/50 rule applies to all income arising.