DWP warns of rule that could cost over £4,500 a year. Brits could lose Carer’s Allowance when claiming state pension, resulting in £81.90 weekly or £4,258.80 annually. Understanding rules crucial to avoid sudden income drop, says expert Suzanne Bourne. It’s advised to apply for Carer’s Allowance even if pension exceeds £81.90. Pension credit can help with living expenses for those with lower incomes. Full new state pension is £221.20 a week, while basic state pension pays £169.50 a week.