Three-Digit Addition With Regrouping
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Prints on one US Letter page; the answer key is a separate page. Print at 100% / "Actual size" on US Letter paper. Free for personal and classroom use. Version 1 of 10. Choose another version.
Skill: Adding three-digit numbers with regrouping, sums up to 999
10 versions, each with its own answer key
Same skill and layout, a fresh set of problems in every version, so children can keep practicing without repeating a page. Problems are not repeated between versions unless a skill has only a small number of possible problems (for example, the addition facts within 10).
- Version 1: Sheet · Key · Both
- Version 2: Sheet · Key · Both
- Version 3: Sheet · Key · Both
- Version 4: Sheet · Key · Both
- Version 5: Sheet · Key · Both
- Version 6: Sheet · Key · Both
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- Version 8: Sheet · Key · Both
- Version 9: Sheet · Key · Both
- Version 10: Sheet · Key · Both
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About this worksheet
Once two-digit addition with regrouping feels solid, three-digit addition is the natural next step. Students must line up hundreds, tens, and ones, then regroup whenever a column adds to ten or more. This second-grade worksheet gives sixteen vertical three-digit plus three-digit problems. Every problem requires regrouping in at least the ones or the tens, and every sum stays at 999 or less so students stay inside numbers they can model with base-ten blocks.
Understanding that ten ones make a ten and ten tens make a hundred is the heart of the skill. Students who only memorize "carry the one" without place-value meaning often misplace digits when problems get longer.
How to use it: have students write the problems in neat columns first. Add the ones, then the tens, then the hundreds, recording each regrouped ten or hundred above the next column. Base-ten blocks or quick sketches of hundreds flats, tens rods, and ones cubes make the trades visible. Estimating first (about 300 + 400) helps catch answers that are far off.
The separate answer-key PDF lists every sum in order. If an answer is exactly 100 or 10 too small, the student likely forgot a regrouped hundred or ten. This worksheet supports Common Core standard 2.NBT.B.7 (add and subtract within 1000 using concrete models or drawings and strategies based on place value). Use it after our Two-Digit Addition With Regrouping worksheet.
