Missing Addend Worksheets

Missing addend worksheets help Grade 1 and Grade 2 students solve addition equations where one of the numbers being added is unknown. These problems build on basic addition by teaching kids to think flexibly about numbers — using subtraction to work backward and find the missing piece. Each worksheet mixes picture-counting, number lines, and straightforward equations, with a complete answer key included so kids can check their work.

Missing Addend Worksheets PDF: Examples

These worksheets ask kids to find the missing number in an addition equation using a mix of formats — counting pictures like apples, candies, or cans, filling in blanks with the help of a number line, and solving straightforward equations such as 18 + ? = 30. Problems start with single-digit sums and build up to double-digit totals, giving kids practice at a range of difficulty levels. Each worksheet includes a complete answer key so kids can check their work.

Missing Addend Worksheets PDF 1

Missing Addend Worksheets PDF 2

Missing Addend Worksheets: Free Download

Download and print Brighterly’s free missing addend worksheets to practice at home or in class. Each worksheet includes a complete answer key, so kids can check their work and see exactly where they need more practice.

Related Worksheets

• Fact Family Worksheets 1st Grade
• Subtraction Facts Worksheets
• Number Bonds Worksheets
• Making 10 Worksheets

Math program

Help your child reach their full potential!

Answer a few quick questions about your child’s learning, and we’ll recommend next steps.

Take the quiz

What’s Inside Brighterly’s Missing Addend Worksheets

Each worksheet mixes a few different problem styles: counting pictures (like apples, candies, or cans) to find a missing addend, filling in blanks using a number line, and straightforward equations like 18 + ? = 30. Problems start with single-digit sums and build up to double-digit totals, so kids can progress from simple addends to more challenging ones without switching worksheets. Every worksheet includes a complete answer key, so kids can check their own work.

How to Find a Missing Addend (8 + ? = 13)

In a missing addend problem, you know one number being added and the total, but not the other number being added. To solve 8 + ? = 13, think of it as a subtraction problem instead: 13 − 8 = 5, so the missing addend is 5. You can check your answer by adding it back: 8 + 5 = 13. Some worksheets also ask the reverse — given two addends, find the total — so it helps to get comfortable moving between addition and subtraction both ways.

Why Practice Missing Addend Problems

Missing addend problems teach kids to think flexibly about addition and subtraction instead of just memorizing one direction of a fact. This flexibility pays off later — once a child is comfortable finding 8 + ? = 13 by working backward, concepts like fact families and multi-step word problems become much easier to pick up.

Frequently Asked Questions

What Grade Are Missing Addend Worksheets For?

Missing addend worksheets are a core Grade 1 skill, extending into Grade 2 as the numbers get larger and problems move from single digits to double digits.

Do These Worksheets Include an Answer Key?

Yes. Every missing addend worksheet includes a complete answer key, so kids can check their work and see exactly where they need more practice.

How Is a Missing Addend Different From a Fact Family?

A missing addend problem asks you to solve for one unknown number in a single equation. A fact family shows all the related addition and subtraction equations that connect the same three numbers — like 8 + 5 = 13, 5 + 8 = 13, 13 − 8 = 5, and 13 − 5 = 8.