Trade license
A state or local plumbing contractor license, often with a licensed master plumber on the company. Licensing rules are set by each state, and sometimes by the county or city, so check what applies where the job is.
Paperwork for plumbing subcontractors, collected and checked.
Plumbing is a licensed trade in most states, and the work is permitted and inspected, so GCs typically collect the license alongside insurance.
Documents GCs typically collect
Certificate of insurance (COI)
General liability and workers’ compensation at the limits your contract or owner requires, plus auto liability when the sub drives to site. Many GCs also ask for additional insured, waiver of subrogation, and primary & non-contributory endorsements.
W-9
For 1099 reporting before the first payment.
References and past projects
Often requested for larger or commercial jobs, or before a first job with a new sub.
Bonding
On public or bonded jobs, a bonding capacity letter and performance and payment bonds may be required, as the contract specifies.
Requirements vary by state, locality, owner and contract. This is a general starting point, not legal or insurance advice. Your contract and local rules decide what’s actually required.
Things to watch
- Gas piping and backflow work can carry separate certifications in some places.
- Ask for current documents per project rather than relying on last year’s file.
How SubSignoff handles it
- Create the project and pick a job type (residential remodel, new home, light commercial, commercial, or public/bonded). SubSignoff prefills typical requirements for that job type, such as insurance types, limits, endorsements, W-9 and license.
- Add Plumbing as a trade on the job. SubSignoff adds Trade license to the packet for that trade and labels where each requirement came from. Everything stays editable.
- Send the sub a portal link. The sub, or their insurance broker, uploads documents from a phone or computer without creating an account.
- Review and track. Check each document against the project’s requirements, approve it, and get reminders before policies and licenses expire.
SubSignoff records what documents say and whether they meet the requirements you set. It doesn’t confirm coverage with insurers or verify licenses with the state. Check licenses with the issuing agency; for some states SubSignoff links to the official lookup page.