Should I amend return for W-2 Box 12 Code E 403(b)

Box 12 Code E on your W-2C refers to elective deferrals under a 403(b) retirement plan. Whether you need to amend your previous year's tax return depends on the specific circumstances:

1. If the increased amount does not affect your taxable income: Contributions to a 403(b) plan are typically pre-tax, meaning they reduce your taxable income. If the correction only updates the amount of contributions reported but does not change your taxable income, you likely do not need to amend your return.
2. If the correction affects your taxable income or deductions: For example, if the increased amount means you exceeded the contribution limit for the year, this could result in additional taxable income. In such cases, you may need to file an amended return to reflect the changes.

I would begin the amend process just so you may tell if you need to amend or not by changing the amount in Box 12 of your W2.