Vertical Column Addition
Column addition is a written method that organises numbers vertically so that digits of the same place value line up in the same column. Once mastered, it works for numbers of any size.
Setting Up Column Addition
Write the numbers one above the other, aligning each digit by place value — ones under ones, tens under tens, hundreds under hundreds, and so on. Draw a horizontal line beneath them, then add each column starting from the right.
Step-by-Step Method
- Write the numbers aligned by place value.
- Add the ones column. Write the result below the line.
- Add the tens column. Write the result below the line.
- Continue left through hundreds, thousands, etc.
Worked Examples
3 4
+ 2 5
-----
5 9
Ones: 4 + 5 = 9. Tens: 3 + 2 = 5. Answer: 59
1 2 4
2 5 1
+ 3 1 3
-------
6 8 8
Ones: 4 + 1 + 3 = 8. Tens: 2 + 5 + 1 = 8. Hundreds: 1 + 2 + 3 = 6. Answer: 688
Aligning Different-Length Numbers
When numbers have different numbers of digits, right-align them. Any empty column to the left counts as zero.
Key Takeaways
- Always right-align (ones under ones, tens under tens).
- Add from right to left — always start with the ones column.
- If a column sums to 10 or more, carry the tens digit to the next column.
- Column addition works for any number of addends and any number of digits.
Practice: Column Addition
Two numbers are set up in column form below. Add them, starting from the ones column. If you get it wrong (or leave it blank), we'll go through each column together.