Year 1 Number Bonds to 20 Worksheets

These Year 1 number bonds to 20 worksheets help children build on their understanding of number bonds to 10 and apply the same thinking to larger totals. Number bonds to 20 are an important KS1 maths skill because they support addition, subtraction, missing number questions and early mental maths fluency.

Children practise finding pairs of numbers that make 20, completing missing number sentences and recognising related addition facts. This helps them understand how numbers can be combined and separated, rather than only memorising individual sums.

Number bonds to 20 help children extend their number fact knowledge and become more confident with addition and subtraction within 20. This topic also supports problem solving because children begin to see links between known facts and new questions.

Parents can use these printable worksheets as regular practice after children are secure with number bonds to 10. Children can complete the worksheet, check answers and then practise saying the facts aloud to improve recall.

Teachers can use number bonds to 20 worksheets for fluency practice, small-group support or revision before moving on to addition and subtraction within 20. Children who understand number bonds to 20 often find missing number questions and mental addition easier.