What does one more mean in math?

One more means the next number when you count upwards. One more than 5 is 6, because 6 comes straight after 5.

What does one less mean?

One less means the number that comes just before. One less than 5 is 4, because 4 comes straight before 5.

Why teach one more and one less?

It helps children understand how numbers grow and shrink by exactly one, which is the foundation for adding, subtracting and using a number line.

One More and One Less | Math

What do "one more" and "one less" mean?

When you count, the numbers go up one step at a time: 1, 2, 3, 4, 5... Each number is just one more than the one before it.

One more means the next number. It is one bigger.
One less means the number before. It is one smaller.

That is the whole idea! Let's see it with some pictures.

One more = one bigger

Imagine three apples on a plate: 🍎 🍎 🍎. That is 3.

Now a fourth apple rolls onto the plate: 🍎 🍎 🍎 🍎. That is 4.

So one more than 3 is 4. Every time you add one more object, the number jumps up by one.

One less = one smaller

Now imagine you have 5 balloons: 🎈🎈🎈🎈🎈.

Pop! One balloon bursts: 🎈🎈🎈🎈.

Now there are 4. So one less than 5 is 4. Every time one object goes away, the number drops by one.

Use the number line

A number line makes one more and one less easy to see. The numbers sit in order along the line.

0 — 1 — 2 — 3 — 4 — 5 — 6 — 7 — 8 — 9 — 10

To find one more, take one step to the right ➡️.
To find one less, take one step to the left ⬅️.

Stand your finger on 6. Step right: you land on 7 — that is one more. Step left from 6: you land on 5 — that is one less. You can practise this on our lesson about the number line.

A handy table

Number	One less	One more
2	1	3
5	4	6
7	6	8
9	8	10

Look closely. The "one less" column is always the number just before, and the "one more" column is the number just after. Three numbers in a row, every time!

Worked example 1: one more

Sam has 7 stickers. His friend gives him one more. How many now?

One more than 7 means the next number. Count on: 7... 8. Sam has 8 stickers. We can write this as 7 + 1 = 8.

Worked example 2: one less

There are 10 ducks on a pond. One duck flies away. How many are left?

One less than 10 means the number before. Count back: 10... 9. There are 9 ducks left. We can write this as 10 − 1 = 9.

Worked example 3: thinking carefully at zero

What is one less than 1? Count back one from 1 and you reach 0. Zero means none — the plate is empty. You cannot have "one less than 0" with real objects, because you cannot have fewer than none. So our counting numbers stop at 0 on this side.

Why this matters

"One more" is really just adding 1, and "one less" is really just taking away 1. So by learning this, you are already doing your very first addition and subtraction!

It also helps you count smoothly. If you know that one more than 8 is 9, you will never get stuck when counting up. This skill leads straight into addition and subtraction with bigger numbers.

Try it yourself

Play the One More, One Less game. You need 10 small objects and a dice or some number cards.

Pick a number card, say 6. Count out that many objects.
A grown-up calls "one more!" — add one object and say the new number: "Seven!"
Then they call "one less!" — take one away and say the new number: "Six again!"
Keep going. Each call, you grow by one or shrink by one.
Challenge: Play with no objects. Just say the answers in your head. How fast can you go?

What's next?

Once one more and one less feel easy, you are ready to count on and back from any number. Try counting backwards and skip counting to build your skills further.

One More and One Less

Key takeaways