< Addition Worksheets

Triple Digit Addition Without Regrouping

Your child has become confident in adding two-digit numbers, so it’s time to start practicing triple-digit addition without regrouping!

It can be scary to see a third digit, but your child has the skills to find these sums! In these worksheets, your student won’t have to worry about carrying digits because each column’s sum will be less than or equal to nine.

Triple-digit addition without regrouping is a great way for students to get comfortable adding larger numbers. It’s also a great time to remind them to start by adding the numbers in the ones column before moving to the tens and finally the hundreds.

Use our triple-digit subtraction without regrouping worksheets too!

How to add triple-digit numbers without regrouping

How do you add three-digit numbers without regrouping?

Note: The steps below are for adding when regrouping isn’t required. If the numbers you’re adding require regrouping, you can head to our triple-digit addition with regrouping page to see step-by-step instructions to follow.

Step 1: Add the numbers in the ones column, and write your answer under the solution bar (in the ones column).
Step 2: Add the numbers in the tens column, and write your answer under the solution bar (in the tens column).
Step 2: Add the numbers in the hundreds column, and write your answer under the solution bar (in the hundreds column).

Example: Find the solution to 345 + 223.

Are there any strategies or tricks for mentally solving three-digit addition problems?

Absolutely!

If you’re adding a number that ends in 9, round up to the nearest 10. Add that number, then subtract one.

- Example: To complete 265 + 129 in your head, turn the 129 into a 130.
  - 265 + 130 = 395 (But this means we’ve added one too many. Just take it away.)
  - 395 – 1 = 394, so 265 + 129 = 394

2. You can follow the same process as above for a number that ends in 8 or 7.

- For 8: Round up to the nearest 10. Add that number, then subtract 2.
- For 7: Round up to the nearest 10. Add that number, then subtract 3.

3. Find groups of 10 and 100.

- To solve 476 + 224, you could first notice that 6 + 4 = 10.
- If you take 4 away from 224 and add it to 476, then you’ll have 480 + 220
- Now, notice that 80 + 20 = 100
- 480 + 220 could be rewritten as 400 + 80 + 200 + 20
- Combine the 80 and 20 to make 100 and you have 400+ 200 + 100 which equals 700.

Triple Digit Addition Without Regrouping

In these worksheets, your student will practice basic addition skills across three place values. Make sure they start in the ones column because working from right to left will make more advanced addition problems much easier! All of our worksheets include an answer key!