Some owners and GCs only accept bids from approved firms. The form asks about your finances, safety record, bonding capacity, licenses and past projects.
A mechanical sub may need approval from a school district before bid day. The deadline for the form often falls well before the bid date.
Read the instructions to bidders early. Find the prequalification deadline first. Keep a current file of references, insurance certificates and a safety summary so the form goes fast.
Requirements differ by owner and by state. Check the bid documents for the exact rules.