You don't have to share your W-2s, but it's unlikely you'll go further

in the hiring process if you don't. The moment you don't share construction salary

information with people, they become alarmed.

Used for income-tax purposes, annual W-2 forms list the wages you were paid and taxes that were withheld by an construction employer. Asking for a prospect's W-2 forms is common in the financial construction industry and in other fields, particularly for sales jobs and at larger companies.