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3rd Grade Addition Worksheets

This free printable worksheet practices adding three-digit numbers. It has 24 problems, and the answer key is on its own page when you print, so you can check work afterward.

Tip: Line up the digits by place value before adding, and regroup when a column adds up to 10 or more.

Name: ____________________Date: ____________

3rd Grade Addition

  1. 405 + 900 = ____
  2. 897 + 849 = ____
  3. 282 + 304 = ____
  4. 836 + 107 = ____
  5. 461 + 928 = ____
  6. 545 + 567 = ____
  7. 862 + 549 = ____
  8. 840 + 818 = ____
  9. 327 + 993 = ____
  10. 614 + 124 = ____
  11. 976 + 180 = ____
  12. 224 + 121 = ____
  13. 660 + 506 = ____
  14. 354 + 138 = ____
  15. 888 + 325 = ____
  16. 803 + 916 = ____
  17. 880 + 398 = ____
  18. 386 + 929 = ____
  19. 614 + 693 = ____
  20. 498 + 440 = ____
  21. 652 + 610 = ____
  22. 710 + 716 = ____
  23. 777 + 380 = ____
  24. 248 + 571 = ____

Answer Key: 3rd Grade Addition

  1. 1305
  2. 1746
  3. 586
  4. 943
  5. 1389
  6. 1112
  7. 1411
  8. 1658
  9. 1320
  10. 738
  11. 1156
  12. 345
  13. 1166
  14. 492
  15. 1213
  16. 1719
  17. 1278
  18. 1315
  19. 1307
  20. 938
  21. 1262
  22. 1426
  23. 1157
  24. 819

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More 3rd grade worksheets: 3rd Grade Subtraction · 3rd Grade Multiplication · 3rd Grade Division · 3rd Grade Fractions · 3rd Grade Place Value · 3rd Grade Rounding · 3rd Grade Area and Perimeter · 3rd Grade Word Problems