Subtracting Decimals: Column Method

D8Subtracting Decimals

Line up the points. Subtract column by column.

Subtracting decimals uses column subtraction with the points lined up.

5.6 − 2.35 = ?

 5.60
−2.35
 3.25

Pad 5.6 to 5.60 first — then exchange and subtract as normal → 3.25

Learn the 3-Step Method

1Line up the decimal points.

Bigger number on top, points in a straight column.

5.6
2.35

2Pad with zeros.

5.6 → 5.60. Every column must have a digit before you subtract.

5.60
2.35

3Subtract with exchanging.

0 − 5 needs an exchange: borrow from the tenths. Work right to left.

3.25

💡 Key IdeaThe padded zero isn't optional — without it, children skip the hundredths column and lose the exchange. 5.60 − 2.35 = 3.25.

Worked Example

Work out 7.2 − 3.85.

Set up & pad

 7.20
−3.85

→

Hundredths

0 − 5: exchange → 10 − 5 = 5

→

Tenths, then ones

1 − 8: exchange → 11 − 8 = 3
6 − 3 = 3

→

✓ Answer

3.35

✓ Check by adding back: 3.35 + 3.85 = 7.2 ✓

Watch Out! Common Mistakes

Skipping the padding zero.

5.6 − 2.35 = 3.35 ✕

Wrong! Without padding, children subtract 5 hundredths from nothing. Pad to 5.60: the answer is 3.25.

Subtracting the smaller digit from the bigger.

0 − 5 → “5” ✕

Wrong! You can’t flip the digits. Exchange from the next column: 10 − 5 = 5.

Forgetting to reduce after exchanging.

7.20 − 3.85 = 3.45 ✕

Wrong! After borrowing, the tenths digit drops by 1. Correct answer: 3.35.

⬇ Cheat Sheet

SUBTRACTING DECIMALS

Bigger number on top; line up the points.
Pad with zeros so lengths match.
Subtract right to left, exchanging when needed.
Check by adding your answer back.

Examples: 5.6 − 2.35 = 3.25 · 7.2 − 3.85 = 3.35

📖 Continue Your Journey

✓ D1 What Are Decimals?✓ D2 Place Value in Decimals ✓ D3 Decimals on a Number Line ✓ D4 Comparing Decimals ✓ D5 Ordering Decimals ✓ D6 Rounding Decimals ✓ D7 Adding Decimals D8 Subtracting Decimals D9 Multiplying by 10, 100 and 1000 D10 Dividing by 10, 100 and 1000 D11 Multiplying Decimals by Whole Numbers D12 Dividing Decimals by Whole Numbers D13 Fractions to Decimals D14 Decimal Problem Solving

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Next Lesson: D9 Multiplying by 10, 100 and 1000The digits slide left. The number gets bigger.

📄 Free printable: Download the Subtracting Decimals cheat sheet (PDF) — keep it by your child's desk.

Quick summary

Line up the decimal points, bigger number on top.
Pad with zeros: 5.6 becomes 5.60 before subtracting.
Exchange (borrow) right to left exactly as in whole-number subtraction.
Check by adding your answer back to the number you subtracted.

Frequently asked questions

How do you subtract decimals with different lengths?

Pad the shorter number with zeros first — 5.6 becomes 5.60 — then use normal column subtraction with the decimal points lined up. 5.60 − 2.35 = 3.25.

What is exchanging in subtraction?

When the top digit is smaller than the bottom one, you borrow 1 from the next column to the left, turning (for example) 0 − 5 into 10 − 5, and reduce that next column by 1.

How can children check a subtraction answer?

Add the answer back: if 7.2 − 3.85 = 3.35, then 3.35 + 3.85 should equal 7.2. If it doesn't, a step went wrong.

D9 Multiplying by 10, 100 and 1000