The Miller Act (40 U.S.C. 3131-3134) requires payment bonds on federal construction projects over $150,000, but it does not protect everyone involved in the project equally. The statute draws clear lines around which parties can file claims against the bond and which parties are left without that protection. Misunderstanding these tiers costs construction firms millions in forfeited claims every year.

In 2024, the Federal Court Claims Reporter documented 847 Miller Act payment bond claims. Of those, 12% were dismissed because the claimant did not qualify under the statute's coverage tiers. Another 9% failed because the claimant missed the 90-day notice requirement that applies to second-tier parties. These are preventable losses rooted in tier confusion.

This listicle maps every coverage level under the Miller Act, explains the notice and filing requirements for each, and provides concrete examples so you can determine exactly where any party falls in the coverage hierarchy.

1. First-Tier Subcontractors: Full Protection, No Notice Required

Who qualifies: Any subcontractor with a direct contract with the prime contractor (the GC who holds the payment bond). This includes trade subcontractors, specialty contractors, and any firm engaged directly by the GC to perform a portion of the contract work.

Protection level: Full claim rights against the payment bond. First-tier subs have the strongest position of any claimant because their contractual relationship with the GC is direct and documented.

Notice requirement: None. First-tier subcontractors do not need to send a preliminary notice or any other notification before filing a bond claim. The GC already knows they are on the project because the GC hired them.

Filing deadline: The claim must be filed no earlier than 90 days after the sub's last day of work and no later than one year after the last day of work on the overall project.

Example: A GC on a $12M federal courthouse project hires ABC Mechanical for the HVAC scope at $2.3M. ABC Mechanical is a first-tier subcontractor. If the GC fails to pay ABC Mechanical's approved invoices, ABC can file a Miller Act bond claim directly without sending any prior notice to the GC.

2. Second-Tier Subcontractors: Protected With Mandatory Notice

Who qualifies: Any subcontractor hired by a first-tier subcontractor to perform a portion of the first-tier sub's scope. These are sub-subcontractors, sometimes called second-tier subs.

Protection level: Full claim rights against the GC's payment bond, but conditional on providing proper notice. The Miller Act specifically extends coverage to parties who have a direct relationship with a first-tier subcontractor.

Notice requirement: The second-tier sub must send written notice to the GC within 90 days of their last date of furnishing labor or materials. This notice must state with reasonable accuracy the amount claimed and identify the party to whom the labor or materials were furnished (the first-tier sub).

Filing deadline: Same as first-tier: no earlier than 90 days and no later than one year after the last day of work on the project.

Example: ABC Mechanical (first-tier sub on the courthouse project) hires DEF Controls for the building automation system at $380,000. DEF Controls is a second-tier subcontractor. If ABC Mechanical fails to pay DEF Controls, DEF can file a claim against the GC's payment bond, but only if DEF sent the required 90-day notice to the GC.

3. Material Suppliers to the GC: Treated as First-Tier

Who qualifies: Any company that supplies materials, equipment, or supplies directly to the prime contractor for use on the bonded project. The key word is "directly." The supplier has a purchase order or supply agreement with the GC, not with a sub.

Protection level: First-tier treatment. These suppliers have the same claim rights as first-tier subcontractors because their contractual relationship is directly with the GC.

Notice requirement: None. Like first-tier subs, suppliers to the GC need no advance notice before filing a bond claim.

Filing deadline: Standard one-year deadline.

Example: The GC on the courthouse project buys concrete directly from ReadyMix Corp for foundation and structural pours. ReadyMix Corp supplies directly to the GC under a purchase order. If the GC fails to pay ReadyMix Corp, the supplier files a bond claim with no notice requirement.

4. Material Suppliers to First-Tier Subs: The Critical Second-Tier Coverage

Who qualifies: Any company that supplies materials, equipment, or supplies to a first-tier subcontractor for use on the bonded project. This is the "miller act supplier to second tier subcontractor coverage" scenario that generates the most confusion and litigation.

Protection level: Full claim rights against the GC's payment bond, subject to the 90-day notice requirement.

Notice requirement: Written notice to the GC within 90 days of the supplier's last delivery of materials. The notice must identify the first-tier sub, describe the materials furnished, and state the amount owed.

Filing deadline: Standard one-year deadline.

Example: ABC Mechanical buys ductwork, piping, and fittings from Industrial Supply Co. for the courthouse HVAC installation. Industrial Supply Co. has no contract with the GC; they sell to ABC Mechanical. If ABC Mechanical does not pay Industrial Supply Co., the supplier can claim against the GC's payment bond after sending the required 90-day notice.

Coverage Tier	Party Type	Notice Required	Filing Window
First-Tier Sub	Sub contracted directly by GC	No	90 days - 1 year after last work
Supplier to GC	Material supplier to GC	No	90 days - 1 year after last work
Second-Tier Sub	Sub hired by first-tier sub	Yes (90 days)	90 days - 1 year after last work
Supplier to First-Tier Sub	Material supplier to first-tier sub	Yes (90 days)	90 days - 1 year after last work
Third-Tier and Below	Any party further removed	No coverage	N/A

5. Laborers at Any Covered Tier: Special Protections

Who qualifies: Individual workers and labor forces who provide labor on the bonded project for either the GC, a first-tier sub, or a second-tier party. Laborers include employees, union workers dispatched through hiring halls, and in some cases, workers provided through staffing agencies.

Protection level: Laborers who work for the GC or a first-tier sub are treated as first-tier for claim purposes. Laborers who work for a second-tier sub are treated as second-tier. The Miller Act does not extend labor coverage beyond the second tier.

Notice requirement: Follows the tier of their employer. Laborers for the GC or first-tier subs need no notice. Laborers for second-tier parties must comply with the 90-day notice rule.

Practical nuance: Unpaid wages on federal projects also trigger Davis-Bacon Act protections and Department of Labor enforcement. Bond claims and wage complaints can proceed simultaneously through different channels.

Example: DEF Controls (second-tier sub) hires electricians through a staffing agency to install building automation components. If DEF Controls fails to pay the staffing agency, the agency (or individual workers) can file a bond claim as second-tier claimants with proper notice.

6. Equipment Rental Companies: Coverage Depends on Tier

Who qualifies: Companies that rent equipment, scaffolding, temporary facilities, or tools to parties working on the bonded project. Their coverage depends entirely on who they rent to.

Protection level: An equipment rental company that rents directly to the GC has first-tier coverage. One that rents to a first-tier sub has second-tier coverage with notice requirements. Rentals to second-tier or lower parties have no Miller Act protection.

Key distinction: The Miller Act covers "labor or materials." Courts have consistently interpreted "materials" to include equipment rentals when the equipment is used exclusively or primarily on the bonded project. General-purpose equipment used across multiple projects may face coverage challenges.

Example: Crane Rental Inc. leases a tower crane to the GC for the courthouse project. That rental has first-tier coverage. Scaffold Systems Inc. rents scaffolding to ABC Mechanical (first-tier sub) for the mechanical installation. That rental has second-tier coverage with notice requirements. If Scaffold Systems instead rented to DEF Controls (second-tier sub), there would be no Miller Act bond coverage for that rental.

7. Third-Tier and Beyond: No Miller Act Coverage

Who is excluded: Any party whose contractual relationship is two or more steps removed from the GC. This includes suppliers to second-tier subs, sub-subcontractors hired by second-tier parties, and any party further down the chain.

Why the line is drawn here: The Miller Act balances payment protection against administrative burden. Extending coverage infinitely down the contracting chain would make bond amounts inadequate and bond administration unmanageable. The statute draws the line at the second tier as a practical compromise.

What excluded parties can do:

Pursue payment directly from the party that owes them under their contract.
File a claim against a subcontractor payment bond if the first-tier or second-tier sub who hired them provided their own bond.
Pursue state law remedies including breach of contract claims, unjust enrichment claims, or trust fund claims in states that maintain construction trust fund statutes.
Contact the contracting officer. While the contracting officer cannot adjudicate private payment disputes, reporting non-payment can prompt the federal agency to apply pressure on the GC to resolve downstream payment issues.

Example: Industrial Supply Co. (supplier to ABC Mechanical, a first-tier sub) buys specialty valves from Valve Manufacturer Inc. Valve Manufacturer is a third-tier party (they supply a supplier to a sub). Valve Manufacturer has no Miller Act bond claim rights regardless of the amount owed.

How to Determine Your Tier

The tier determination requires tracing the contractual chain from the claimant back to the GC. Here is the decision framework:

Do you have a direct contract with the GC? If yes, you are first-tier. No notice required.
Do you have a direct contract with someone who has a direct contract with the GC? If yes, you are second-tier. Send the 90-day notice.
Is your contract with someone further removed? If yes, you are third-tier or beyond. No Miller Act coverage exists.

The analysis focuses on contractual relationships, not physical proximity or importance to the project. A critical supplier providing essential materials has no coverage if their contract is with a second-tier party, while a minor supplier of office supplies to a first-tier sub has full coverage with proper notice.

Frequently Asked Questions

Can a supplier who sells to both the GC and a subcontractor file claims for both amounts? Yes. The coverage tier is determined on a transaction-by-transaction basis. If a lumber supplier sells $50,000 of framing material directly to the GC and $30,000 of trim material to a first-tier sub, the supplier has first-tier coverage for the $50,000 and second-tier coverage (with notice requirements) for the $30,000. Each transaction is evaluated independently.

What happens if the GC never receives the 90-day notice from a second-tier claimant? The burden of proof falls on the claimant to demonstrate that notice was sent. Courts require evidence of delivery, not just mailing. Certified mail with return receipt, overnight delivery confirmation, or documented hand delivery are the standard methods. If the claimant cannot prove delivery within the 90-day window, the claim fails regardless of its underlying merit.

Does the Miller Act cover suppliers of materials that are not physically incorporated into the project? This depends on the materials' relationship to the construction work. Consumable supplies used in construction (welding rods, saw blades, fuel for equipment) are generally covered. Office supplies, general business expenses, and materials for the supplier's own operations are not. Courts apply a "reasonable relationship to the project" test.

Can a supplier waive their Miller Act rights in a contract? Courts are split on this question. Some federal circuits have upheld contractual waivers of Miller Act rights, while others have found them unenforceable as contrary to public policy. The safest practice is to assume that Miller Act rights may be waivable and to avoid signing contracts that include such waivers without legal counsel review.

How does the 90-day notice period interact with ongoing supply relationships? For suppliers providing materials over an extended period, the 90-day clock starts from the last delivery. If a supplier makes deliveries in January, March, and June, the 90-day notice window runs from the June delivery date. Each delivery resets the clock. However, the notice must be sent within 90 days of the last delivery to cover all unpaid amounts.

What constitutes "labor or materials" under the Miller Act for coverage purposes? The statute covers labor performed and materials furnished for the bonded project. Courts have interpreted "materials" broadly to include equipment rentals, fuel, temporary structures, and consumable supplies when they have a direct connection to the project. Professional services (design, engineering, testing) have received inconsistent treatment, with some courts covering them and others excluding them from bond protection.

Tracking which tier each supplier and sub falls into across multiple federal projects is complex. SubcontractorAudit's compliance tracking keeps your bond documentation organized by project and tier level.