When money is lent between family members, mortgage lenders and HMRC may require written evidence that it is a loan (repayable) rather than a gift (not repayable). A gift letter or loan agreement is commonly required by mortgage lenders. Without documentation, family disputes over repayment are common.

• Mortgage lenders often require a "gifted deposit letter" OR loan agreement
• If it's a loan: appears as a liability on mortgage application — may affect affordability
• Interest on family loans: HMRC may impute interest if loan is to a company
• Inheritance tax: gifts made more than 7 years before death fall outside estate
• Put it in writing even between family — protects everyone

Legal reference: Inheritance Tax Act 1984 (PETs); HMRC IHT400; mortgage lender affordability rules