Subtraction Within 20 Worksheets — KS1
Subtraction is one of the four fundamental operations that KS1 children must master. The National Curriculum requires Year 1 children to subtract one-digit and two-digit numbers to 20 and Year 2 children to subtract numbers using concrete objects, pictorial representations, and mentally. Our subtraction worksheets within 20 build these skills progressively, from early counting back strategies to efficient mental methods.
Generate a Custom Subtraction Worksheet
Create a personalised worksheet for Key Stage 1 in seconds. Free to try — no card required.
Key Skills Covered
Three Models of Subtraction
Subtraction has three distinct meanings that children must understand: taking away (I have 15, I lose 6, how many left?), finding the difference (Tom has 18 stickers, Sam has 12 — what is the difference?), and counting up (from 9 to 15 — how many steps?). Our worksheets cover all three models so children develop a flexible understanding, not just rote-learned procedures.
From Counting Back to Efficient Strategies
Early subtraction involves counting back on fingers or a number line. As children develop, they should move to using known number bonds (15 – 8 = ? because 8 + 7 = 15) and bridging through 10 (17 – 9 = 17 – 7 – 2 = 10 – 2 = 8). Our worksheets explicitly teach these strategies with step-by-step worked examples before asking children to practise independently.
Sample Questions
17 – 9 = ?
Show answer
8
20 – ? = 13
Show answer
7
What is the difference between 16 and 7?
Show answer
9
There are 18 biscuits. Sam eats 6. How many are left?
Show answer
12 biscuits
? – 8 = 11
Show answer
19
More Subtraction Resources for Key Stage 1
Ready to Create Your Worksheet?
Generate a custom subtraction worksheet for Key Stage 1 in seconds. Free to try — no credit card required.
Generate Free Worksheet