Last updated: August 2026

W-2 & Payroll Reporting. Box 12 Codes, Corrections & Filing

W-2 errors create downstream problems. Wrong Box 12 codes affect employee tax returns, missing corrections trigger IRS notices, and reporting failures compound with penalties.

Reading the W-2 boxes

• W-2 Box 12 codes every code from A to HH and the ones that get miscoded most often
• W-2 Box 14 codes what the common entries mean and which of them are taxable
• Imputed income and group term life how employer paid coverage becomes taxable wages under IRC Section 79

Corrections and special reporting

• The W-2c correction form when a correction is required, the W-3c transmittal, and the timing issue for the employee return
• Third party sick pay how reporting splits depending on whether the insurer acts as agent, plus Form 8922