Marriage Allowance is a simple but powerful way for married couples or civil partners to reduce their income tax bill, yet so many people don’t use it. If one partner earns below the Personal Allowance and the other is a basic rate taxpayer, you could transfer part of that unused allowance and save money every tax year. Here’s how it works. The partner with the lower income can transfer 10% of their Personal Allowance to their spouse or civil partner. The Personal Allowance is currently £12,570,