Year 1 Maths: Free Printable Number Bonds to 20 Worksheets With Answers

Why number bonds to 20 matter in Year 1

Number bonds are pairs of numbers that add together to make a total. In Year 1, children begin by learning bonds to 10, then build towards recognising and using bonds to 20. They might know that 7 and 3 make 10, for example, and use this understanding to see that 7 and 13 make 20.

These facts are a foundation for addition and subtraction. When children can recall them with growing confidence, they have more attention available for solving problems, explaining their thinking and working with larger numbers later on. The aim is not simply to complete a worksheet quickly. Children need to understand how the numbers fit together, practise in varied ways and develop accurate recall over time.

Free printable number bonds to 20 worksheets can provide useful, focused practice at home or in the classroom. Used alongside objects, pictures and conversation, they give children opportunities to revisit familiar facts and notice patterns.

What the National Curriculum expects

The England National Curriculum for mathematics expects pupils in Year 1 to read, write and interpret mathematical statements involving addition and subtraction, using the signs +, − and =. Children work with numbers up to 20 and are taught to represent and use number bonds and related subtraction facts within 20.

In practice, this means children should learn that a total can be made in different ways. For example, 20 can be split into 12 and 8, or 15 and 5. They should explore these combinations using practical resources and pictures before moving towards writing number sentences such as 12 + 8 = 20 and 20 − 12 = 8.

The curriculum also encourages children to solve one-step problems involving addition and subtraction. Number bonds support this work because they help children identify missing numbers and choose a suitable calculation. A child might be asked, “There are 20 spaces and 14 are filled. How many are empty?” Recognising that 14 and 6 make 20 helps make the problem manageable.

Year 1 pupils develop at different rates. Some will confidently recall many bonds to 20, while others are still securing bonds to 10 or counting reliably. Short, successful practice is more helpful than expecting every child to memorise all the facts at once.

How to use printable worksheets effectively

Choose worksheets with a clear layout and a manageable number of questions. A page might ask children to complete missing numbers, match pairs to a total, or write the number sentence that fits a picture. Mixing question types helps children think about the relationship between numbers rather than copying a single pattern.

Begin with facts your child or pupils already know. If bonds to 10 are secure, use them to introduce bonds to 20. For instance, children can use 6 + 4 = 10 to help them work out 6 + 14 = 20. Point out that the smaller number stays the same while the partner changes by 10. This connection can make larger bonds easier to understand.

Before handing over a worksheet, try a few examples together with counters, cubes, buttons or toys. Make a group of 20 objects and split it into two parts. Ask, “How many are here? How many more would make 20?” Then record the answer as a number sentence. Children who can see and move the quantities often find the written task less abstract.

Keep practice brief and positive. Five or ten minutes at a time is usually enough for a Year 1 child, particularly if they are new to the facts. Stop if attention is fading, and return to the worksheet another day. Regular revision in short sessions is more useful than a long drill that leaves a child tired or frustrated.

Helpful ways to practise number bonds

Make the missing number the focus. Write 9 + □ = 20 and invite the child to use counters, count on or recall a known fact. Ask them to explain how they found the answer. A simple explanation such as “9 needs 1 to make 10, then 10 more makes 20, so it is 11” shows useful reasoning, even if the child needs support to express it.

Use everyday moments as well as worksheets. At snack time, ask how many pieces are needed to make 20. With toy cars, make two groups and find how many are in each part. In the classroom, children could count how many pupils are present and work out how many spaces remain in a group of 20. These real situations help children see that number bonds are useful, not just a school exercise.

Games can add variety to revision. Place number cards face down and take turns finding two that make 20. Alternatively, say a number and ask the child to respond with its partner: “I have 13; what do I need to make 20?” Let the child use a number line or counters at first, then encourage recall as confidence grows. Keep the pace relaxed and praise careful thinking, not just speed.

A useful visual aid is a part–whole model: write 20 in the whole box and place one part in a smaller box. The child fills in the missing part. Ten frames, bead strings and number lines can also help. Choose one or two representations and use them consistently so that the child can focus on the numbers rather than learning a new layout each time.

Using worksheet answers to support learning

An answer sheet is most helpful when it prompts discussion. After a child completes a worksheet, check a few questions together and ask how they know an answer is correct. If they have made a mistake, avoid simply giving the right number. Return to the objects or drawing and help them find where their thinking changed.

For example, if a child writes 8 + 11 = 20, ask them to count the two parts or use a number line. They may discover that the total is 19 and identify the missing one. Encourage children to check addition and subtraction facts together: if 8 + 12 = 20, then 20 − 8 = 12. This links the operations and reinforces the same number relationship in different ways.

Look for patterns in completed work. Are some bonds easy to recall while others regularly cause difficulty? A child might know 10 + 10 = 20 but need more practice with 7 + 13 or 16 + 4. Use the answers to identify a small group of facts to revisit, rather than repeating the whole worksheet each time.

Supporting different learners

For a child who finds the task difficult, start with bonds to 10 and build upwards using familiar facts. Reduce the number of questions, provide counters and allow plenty of thinking time. A worksheet with a few completed examples can make the instructions easier to follow.

For a child who is ready for more challenge, include missing-number equations in different positions, such as □ + 6 = 20 or 20 − □ = 9. Ask them to write their own number-bond questions or explain a strategy that another child could use. Keep the work appropriate to Year 1 by focusing on clear number relationships rather than speed or unnecessarily large calculations.

A practical next step

Use free printable number bonds to 20 worksheets as one part of a varied routine: model the facts with objects, complete a short practice page, check answers together and revisit tricky pairs during the week. Follow your child’s confidence, celebrate progress and make time for them to explain their thinking. With calm, regular practice and links to the Year 1 National Curriculum, number bonds can become a secure base for addition, subtraction and future maths learning.