Is Code W in box 12 of Form W-2 reported on Form 1040?

Form W-2 is Wage and Tax Statement. Code D refers to elective deferrals to a section 401(k) cash or deferred arrangement. It also includes deferrals under a SIMPLE retirement account that's part of a section 401(k) arrangement. Code D elective deferrals generally are limited to a total of $16,500 ($11,500 if you only have SIMPLE plans). Any amount above the overall elective deferral limit must be included in income on line 7 (Wages/salaries, tips, etc.) of Form 1040.