Number bonds: the bonds to 10 and beyond

A number bond shows how a number splits into two parts: 10 is 7 and 3. The bonds to 10 (1 + 9, 2 + 8, 3 + 7, 4 + 6, 5 + 5) are the most useful facts a young child can learn, because they unlock making 10, fact families and mental math. This page explains them with pictures, a ten frame tool and games.

What a number bond is

The whole sits at the top and the two parts below. Reading it gives addition (7 + 3 = 10) and subtraction (10 − 3 = 7) at once.

7 and 3 make 10.

6 can be 4 and 2.

The bonds to 10

0 + 10

1 + 9

2 + 8

3 + 7

4 + 6

5 + 5

Plus their turn-arounds (9 + 1, 8 + 2…). On a ten frame, the empty boxes always show the other part.

Ten frame: find the partner to 10

Slide to any number. The tool shows its partner to 10 and every way to make it.

How number bonds help

Making 10: 8 + 5 = 8 + 2 + 3 = 13, using the bond 2 + 8.
Subtraction: 10 − 4 = 6, because 4 and 6 make 10.
Bigger numbers: 30 + 70 = 100 uses the same bond 3 + 7.

Common mistakes

“7 and 4 make 10”Guessing.Fix: use a ten frame: 7 filled, count the empty boxes: 3.

Only one way to make a numberThinks 6 is only 3 + 3.Fix: list all the ways: 0 + 6 to 6 + 0.

Counting from 1 every timeHasn’t memorized the bonds.Fix: short daily games until they are instant.

Doesn’t see subtraction in a bondTreats bonds as addition only.Fix: cover one part and ask what is hidden.

How to teach it at home

Hidden objects

Show 10 counters, hide some under a cup. How many are hidden?

Fingers

Hold up 6 fingers: how many are down?

Make 10 with cards

Find card pairs that make 10.

By grade

Kindergarten (K.OA.A.3, K.OA.A.4): split numbers to 10 in different ways and find the partner to 10.
Grade 1 (1.OA.C.6): use making 10 to add and subtract within 20.
Next: addition facts.

Worksheets and practice

Number bonds worksheet: printable PDF with an answer key. · Make a fresh test

Addition to 10 (PDF) · Number sense

Last reviewed October 3, 2026

Questions parents ask

What are number bonds?

Pairs of numbers that make a whole: 7 and 3 make 10. They show how a number can be split into two parts.

What are the number bonds to 10?

0 + 10, 1 + 9, 2 + 8, 3 + 7, 4 + 6 and 5 + 5, plus their turn-arounds.

Why are number bonds important?

They make adding and subtracting fast and are the key to the make-10 strategy and mental math.

How do I teach number bonds?

With ten frames, fingers and hidden-object games, a few minutes every day.

When do kids learn number bonds?

Kindergarten for numbers to 10, and grade 1 uses them for facts to 20.