Year 1 Missing Number Addition Worksheets

These Year 1 missing number addition worksheets help children think more deeply about addition. Instead of only finding the total, children practise finding a missing part in an addition number sentence, which supports reasoning, number bonds and early algebraic thinking.

The worksheets include simple addition facts where one number is missing. This helps children understand that addition is about parts combining to make a whole, and that the missing number can often be found by counting on, using number bonds or thinking about related facts.

Missing number addition helps children move beyond basic calculation and begin reasoning about number relationships. It supports part-whole understanding and prepares children for more advanced problem solving later in KS1.

Parents can use these worksheets at home after children have practised simple addition within 10 or 20. Encourage children to explain what is missing and how they know, rather than only writing the answer.

Teachers can use missing number addition worksheets during fluency sessions, reasoning lessons, intervention groups or revision. Children who understand missing number addition are better prepared for number bonds, subtraction links and inverse operations.