But according to Money Saving Expert (MSE) those with three or more kids aren’t the only ones who miss out — and it’s all down to a simple error in your child benefit application. In the latest edition of its newsletter, the Martin Lewis-founded site shared six things all parents need to know about child benefit, claiming households across the country are losing both money and a boost to their state pension. Child benefit is available for anyone with parental responsibilities for children under 16 or up to 20 in full-time education, with the maximum available coming in at £26.50 a week for your first-born. Because of this, some higher earners decide not to apply — which MSE says is often a big ‘mistake’. How much is child benefit?