Documents to collect from subcontractors: a GC checklist by stage

The checklist at a glance

Before award: prequalification

Prequalification decides whether to hire the sub at all. Commonly requested:

• A prequalification questionnaire: legal name, ownership, years in business, volume, backlog, references, open claims.
• The experience modification rate (EMR). It compares the sub's workers' comp losses with the average employer in the same classification, usually over the latest available three years of data. A 1.00 mod is unity; below it is a credit mod, above it a debit mod.
• OSHA 300A summaries for recent years. A company with 10 or fewer employees at all times during the last calendar year generally does not have to keep OSHA injury and illness records (29 CFR 1904.1), so a small sub may have none.
• A bonding capacity letter from the sub's surety, if the sub will be bonded.
• The trade license, where the state or city licenses the trade. Check status yourself on the issuing board's lookup, such as the CSLB in California or TDLR in Texas, and confirm the holder is the company you are about to sign.

Before mobilization: the onboarding packet

W-9

The W-9 gives AP the name and taxpayer identification number (TIN) it needs for Form 1099-NEC. IRS instructions say a payer must backup withhold 24% of reportable payments to a payee who fails to furnish a TIN, and can be liable for amounts it fails to withhold.

Neither the form nor the IRS instructions set an expiration date. The IRS tells the payee to furnish a new W-9 if the name or TIN changes. See W-9s from subcontractors and W-9 collection.

Certificate of insurance and endorsement pages

The ACORD 25 lists the policies issued to the insured named on the form. The form itself says it confers no rights on the certificate holder, that an additional insured needs policy provisions or an endorsement, and that a statement on the certificate is no substitute for an endorsement. So when your subcontract requires additional insured status or a waiver of subrogation, ask for the endorsement pages, not just a checked box.

Compare the limits with your company, project and vendor minimums. Then read each coverage line's expiration date: general liability can run to next year while auto expires next month. Review every renewal certificate as a new document. See how to read an ACORD 25 and when a sub's COI expires.

Workers' comp proof

In Florida this is the law. Florida Statutes § 440.10(1)(c) says a contractor shall require a subcontractor to provide evidence of workers' compensation insurance; a corporate sub whose officer elected exemption gives the contractor a copy of the exemption certificate. Section 440.10(1)(b) makes the contractor liable for compensation to a sub's employees unless the sub has secured it. Outside Florida, check your state's rules and your subcontract. Sub certificates also come up at your own policy's premium audit.

Subcontract and safety

• Signed subcontract with exhibits: the insurance exhibit, scope, schedule and the lien waiver forms you plan to use. Agreeing on waiver forms now avoids an argument at the first pay app.
• Safety documents: a site-specific safety plan and the sub's written safety program. On a multi-employer site, OSHA's Hazard Communication standard requires an employer whose chemicals could expose other employers' workers to say in its written program how they get on-site access to its safety data sheets (29 CFR 1910.1200(e)(2)(i); 29 CFR 1926.59 for construction).
• OSHA 10 and 30 cards, if your site requires them. OSHA says its Outreach Training Program is voluntary, though some states, cities and employers require it.

Every pay application

A common pattern: a conditional waiver for the payment requested, and an unconditional waiver for the previous payment once it cleared. Some states prescribe the waiver wording, such as California (Civil Code §§ 8132–8138) and Texas (Property Code § 53.284), and a few state forms need a notary or witness. Check your state on lien waiver requirements by state.

Some processes add a sworn statement of who supplied labor and material and what each is owed:

• Michigan: a subcontractor provides a sworn statement to the contractor when payment is due or when it requests payment (MCL 570.1110(3)).
• Illinois: the contractor must give the owner a sworn statement of everyone furnishing labor and material, and the amounts due, before the owner pays (770 ILCS 60/5(a)). A sub must give the contractor its own statement, under oath if required, within 5 days of a written request (770 ILCS 60/22).

For a whole draw's sequence, see closing out a draw; for the four waiver types, conditional vs. unconditional lien waivers.

Public projects add their own paperwork

• Davis-Bacon work. The Department of Labor says contractors and subcontractors on covered federal and federally assisted construction must submit payroll information weekly. Form WH-347 is optional; the weekly payroll is not.
• California public works. To register with the Department of Industrial Relations, a contractor must use only subcontractors who are registered public works contractors. Registration covers one to three fiscal years, each running July 1 to June 30, so check each sub before it starts and again after July 1.

Closeout

Retainage is often your last leverage. Commonly collected before you release it:

• Final lien waivers: a conditional final with the last payment, then an unconditional final once it clears. The final amount should include retainage.
• Warranties: start date (substantial completion or acceptance), coverage and who to call.
• O&M manuals and training sign-offs for installed equipment.
• As-built or record drawings for the sub's scope.
• A current certificate, if the subcontract requires completed-operations coverage after the work ends.

On AIA prime contracts, owner closeout often involves G706 (Contractor's Affidavit of Payment of Debts and Claims), G706A (Contractor's Affidavit of Release of Liens) and, on bonded work, G707 (Consent of Surety to Final Payment). AIA describes G706 as typically executed as a condition of final payment.

One sub, three names

The W-9, the certificate and the lien waiver each name the sub. They often differ, and that can be fine.

• W-9 line 1 and line 2. The IRS says line 1 should match the name on the tax return. A sole proprietor puts their own name on line 1 and the business or DBA name on line 2. A single-member LLC that is a disregarded entity puts the owner's name on line 1 and the LLC's name on line 2. A corporation, partnership or other LLC puts its own name on line 1. The TIN must match the line 1 name to avoid backup withholding.
• ACORD 25 Insured box. The policies are issued to the insured named there. It may show the LLC, a DBA or a parent company.
• Lien waiver claimant. California's statutory forms ask for the Name of Claimant and the Claimant's Signature, and the conditional forms ask who the check is payable to. In Texas, a waiver releases claims only if it is signed by the claimant or the claimant's authorized agent (Property Code § 53.281(b)(2)).

Example: the W-9 shows Maria Ortiz on line 1 and Ortiz Drywall LLC on line 2. The certificate names Ortiz Drywall LLC DBA Ortiz Interiors. The waiver comes from Ortiz Interiors. All three can be the same business, and the W-9 is filled out correctly.

Make this a human review step. When the packet arrives, one person compares the subcontract party, both W-9 lines, the insured and the waiver claimant, decides whether they describe the same business, and writes down why. Ask for a corrected document before you pay if:

• the named insured is a sister or parent company, not the company on your subcontract;
• the waiver claimant is a different business from the party to your subcontract; or
• the check is payable to a name that appears on none of the other documents.

Where SubLien fits

SubLien keeps a sub's W-9, certificates, lien waivers and other documents on one vendor record. W-9s are requested by secure link, kept as the source file and reviewed by a named teammate. For certificates, AI prefills the ACORD 25 fields, SubLien compares them with your minimums, and a named reviewer confirms the result. Each coverage line keeps its own expiration date, and reminders can copy the sub's agent. Lien waivers go out for e-signature with signature evidence, or for upload where the state form needs a notary or witness. Other documents can be requested as an upload, a signature (optionally countersigned by your team) or a notarized return.

SubLien does not read W-9 contents, match TINs with the IRS, file 1099s, check licenses with issuing boards, decide coverage or compliance, or hold payments. See vendor document collection, COI tracking or lien waiver software.

Common questions

What documents should a GC collect from a subcontractor before work starts?

Commonly a W-9, an ACORD 25 certificate with the endorsement pages the subcontract requires, proof of workers' comp, the trade license where one applies, a signed subcontract and a site-specific safety plan.

What should a GC collect from a subcontractor at closeout?

Commonly a conditional final lien waiver with the last payment and an unconditional final once it clears, with retainage included, plus warranties, O&M manuals, as-built drawings, and a current certificate if the subcontract requires completed-operations coverage.

Is a certificate of insurance enough, or do I need the endorsements?

Ask for the endorsements too. The ACORD 25 itself says it confers no rights on the certificate holder and that a statement on the certificate is no substitute for an additional insured or waiver of subrogation endorsement.

Is a GC required by law to collect proof of workers' comp from subs?

In Florida, yes. Statutes § 440.10(1)(c) says a contractor shall require a subcontractor to provide evidence of workers' compensation insurance, and a corporate sub with an exempt officer gives the contractor a copy of the exemption certificate. Other states set their own rules.

What if the names on the W-9, the certificate and the waiver don't match?

Have one person decide whether they describe the same business. An owner's own name on W-9 line 1 is correct for a sole proprietor or a disregarded single-member LLC; a different company as the insured or claimant needs a corrected document.

Primary sources

• IRS Form W-9 (Rev. March 2024): line 1, line 2 and backup withholding.
• IRS Instructions for the Requester of Form W-9: the 24% backup withholding rate.
• Texas Department of Insurance, ACORD 25 specimen: the form's own warnings.
• Florida Statutes § 440.10: evidence of a sub's workers' comp coverage.
• OSHA 29 CFR 1910.1200: multi-employer SDS access.
• OSHA 29 CFR 1904.1: the small-employer exemption.
• OSHA Outreach Training Program: 10- and 30-hour cards.
• NCCI, ABCs of Experience Rating: how the mod is calculated.
• U.S. Department of Labor, Form WH-347: weekly certified payroll.
• California DIR, contractor registration: the registered-subcontractor rule.
• CSLB, statutory waiver forms: California Civil Code §§ 8132–8138.
• Texas Property Code Chapter 53: waiver signing and prescribed forms.
• Michigan MCL 570.1110: sworn statements.
• Illinois 770 ILCS 60/5: the contractor's sworn statement.
• Illinois 770 ILCS 60/22: the subcontractor's statement on request.
• AIA, G706 summary: the affidavit at final payment.
• AIA, G707 and G707A FAQ: consent of surety on bonded work.