Addition · US · Grades 1–3

3-Digit Addition with Regrouping Worksheets

Three-digit plus three-digit addition in columns where every problem carries at least once — sometimes twice, sometimes into a fourth digit. Twenty problems to a page, large enough to write the carries above the columns, with the answer key on page 2.

Problems: 20 · 3-Digit Addition with Regrouping
Regrouping: every problem regroups
Answer key: Included, same positions
Paper size: US Letter (A4 available)

About this worksheet

This is the standard third-grade sheet (and a late second-grade stretch). For a gentler version set Regrouping to "Some problems"; for a harder one go to 4-digit numbers, which are also used for addition within 10,000 in grade 4.

Standards

Common Core 2.NBT.B.7 — add within 1000 using concrete models or strategies
Common Core 3.NBT.A.2 — fluently add and subtract within 1000

Questions

Do the sums go over 1,000?

Yes, when the hundreds carry. If you want all sums under 1,000, that is a sign the class is not yet ready for this sheet; use 2-digit with regrouping and 3-digit without regrouping first.

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