Construction bonding is a financial guarantee, backed by a third-party surety company, that a contractor will finish a project and pay the workers and suppliers on it. Federal law requires performance and payment bonds on government construction contracts over $150,000 under the regulations implementing the Miller Act, with the underlying statute set at contracts over $100,000.1Office of the Law Revision Counsel. United States Code Title 40 3131 – Bonds of Contractors of Public Buildings or Works2Acquisition.GOV. FAR 28.102-1 General Most states impose parallel requirements on their own public projects, and private owners and lenders often demand bonds on large developments as independent proof that the contractor is financially and operationally sound. The point of the system is to shift the risk of contractor failure off the owner and onto a well-capitalized third party.
Who the Three Parties Are
Every bond involves three parties, and the labels matter because they determine who owes what to whom.
The principal is the contractor. The principal buys the bond and remains responsible for the underlying obligations no matter what the surety pays out.
The obligee is the party the bond protects. On public work that’s the government agency; on private work it’s the owner. When something goes wrong, the obligee (or, on payment bonds, unpaid lower-tier parties) has a financial backstop.
The surety is the company guaranteeing the principal’s obligations. A surety isn’t handing the contractor free money. It’s extending credit, pledging its own balance sheet to cover the contractor’s commitments. If it pays a claim, it has the legal right to recover every dollar from the contractor. That recovery right is the core difference between a bond and an insurance policy: the contractor is always on the hook.
A fourth player worth knowing is the bond producer, the licensed intermediary who assembles the underwriting file and advocates for the contractor with the surety. For a growing firm pushing into larger projects, a capable producer is often the difference between getting bonded and getting declined.
The Main Types of Construction Bonds
Different bonds cover different risks at different stages of a project.
Bid Bonds
A bid bond guarantees that a contractor who wins a competitive bid will actually sign the contract and post the required performance and payment bonds. If they back out, the surety pays the owner the difference between the winning bid and the next lowest qualified bid, up to the bond’s limit. On federal projects, the bid guarantee must be at least 20 percent of the bid price, capped at $3 million.3eCFR. 48 CFR 28.101-2 – Solicitation Provision or Contract Clause Private owners commonly set bid bonds at 5 to 10 percent of the bid price.
Performance Bonds
Once the contract is signed, the performance bond guarantees that the contractor will complete the work according to specifications, on time and within scope. If the contractor defaults, the surety may finance them to get back on track, hire a replacement to finish, or pay the owner up to the bond’s penal sum. On federal contracts, the performance bond equals 100 percent of the contract price.4Acquisition.GOV. 52.228-15 Performance and Payment Bonds – Construction
Payment Bonds
The payment bond guarantees that the contractor will pay its subcontractors, laborers, and material suppliers. On private projects, unpaid workers and suppliers can file mechanics’ liens against the property to force payment. You can’t lien government-owned property, so on federal projects the payment bond is the only route for these parties to recover.5U.S. General Services Administration (GSA). The Miller Act Brochure The federal payment bond penal sum is also 100 percent of the contract price.4Acquisition.GOV. 52.228-15 Performance and Payment Bonds – Construction
Maintenance and Warranty Bonds
After the owner accepts the completed work, a maintenance bond covers defects in materials or workmanship during a defined warranty period. On federal contracts, the standard warranty runs one year from final acceptance, and repaired or replaced work restarts that one-year clock.6Acquisition.GOV. Warranty of Construction Many performance bonds include coverage for the standard one-year period; longer warranties usually cost extra premium and may require a separate maintenance bond.
When Bonding Is Required
The Miller Act, enacted in 1935 and now codified at 40 U.S.C. §§ 3131–3134, is the backbone of federal construction bonding law. It requires both a performance and a payment bond on federal construction contracts over $100,000.1Office of the Law Revision Counsel. United States Code Title 40 3131 – Bonds of Contractors of Public Buildings or Works The Federal Acquisition Regulation raises the mandatory bonding threshold to $150,000 in practice.2Acquisition.GOV. FAR 28.102-1 General
Every state has its own version, commonly called a “Little Miller Act,” extending bonding requirements to state and municipal public work. Thresholds vary by jurisdiction, with most falling between $25,000 and $100,000. There is no universal bonding mandate on private projects, but on large developments lenders and owners frequently require bonds anyway.
Deadlines for Unpaid Subs and Suppliers on Federal Projects
If you’re an unpaid subcontractor or supplier on a Miller Act project, the payment bond gives you a right to sue, but only if you follow strict deadlines. A first-tier subcontractor or supplier (someone with a direct contract with the prime) doesn’t need to send preliminary notice. They can file suit on the bond after 90 days have passed since they last performed work or delivered materials, and they must file within one year of that date.7Office of the Law Revision Counsel. United States Code Title 40 3133 – Rights of Persons Furnishing Labor or Material
Second-tier parties (those who contracted with a subcontractor rather than the prime) have an added hurdle. They must send written notice to the prime contractor within 90 days of last furnishing labor or materials, identifying the amount claimed and the party they worked for. The same one-year filing deadline applies from the last-work date.7Office of the Law Revision Counsel. United States Code Title 40 3133 – Rights of Persons Furnishing Labor or Material Missing the 90-day notice window destroys the claim. This is where most lower-tier bond claims fall apart: by the time a supplier realizes they’re not being paid, the notice period has quietly closed.
What It Takes to Qualify
Getting bonded is closer to getting a loan than buying insurance. The surety is putting its own capital at risk, and underwriters evaluate contractors on what the industry calls the Three Cs.
Character covers reputation and track record: project history, references from owners and architects, the personal credit of the company’s principals, and any pattern of claims, disputes, or unfinished work.
Capacity is operational fit for the specific project. The surety looks at the experience of key personnel, the equipment the company owns or leases, and whether the organization can support the size and complexity of the job. A paving contractor bidding on a high-rise will face hard questions.
Capital is financial health. Underwriters review financial statements (often CPA-prepared or audited) for working capital, balance-sheet ratios, and consistent profitability. They also review a work-in-progress schedule listing every current contract with projected costs, revenues, and profit or loss. That schedule tells the surety whether the contractor is spread too thin.
The General Indemnity Agreement
Before any bonds are issued, the surety requires the company and typically its individual owners to sign a General Indemnity Agreement. The GIA obligates the signers to reimburse the surety for every dollar paid on a claim, plus investigation costs and legal fees. Personal indemnity means owners can’t hide behind the corporate structure. Spouses and affiliated companies are often asked to sign as well. No GIA, no bonds.
Single-Job and Aggregate Limits
Once approved, a contractor is assigned two limits. The single-job limit is the largest individual project the surety will bond. The aggregate limit is the maximum total backlog of bonded work the contractor can carry at once. A contractor with a $5 million single-job limit and a $25 million aggregate can take any individual project up to $5 million so long as total bonded backlog stays under $25 million. Going above either number requires special underwriter approval.
What Bonds Cost
Bond premiums are a percentage of the contract price, and the percentage depends on the contractor’s financial strength, credit history, project size, and type of work. Established contractors with strong financials and clean records typically pay 1 to 3 percent of contract value for combined performance and payment bonds. Weaker profiles can push the rate to 3 to 5 percent or higher. Sureties usually apply a tiered structure where the rate drops as contract value rises, so a $50 million job carries a lower rate per dollar than a $2 million one.
Personal credit matters. Scores above 700 generally unlock the best rates. Between 650 and 700 the deal still works, but premiums climb and documentation requirements tighten. Below 650, standard surety markets become difficult to access. Some sureties will issue bonds regardless of credit if the contractor posts collateral (cash, a certificate of deposit, or an irrevocable letter of credit), but that ties up capital the contractor may need elsewhere.
The SBA Surety Bond Guarantee Program
Small and emerging contractors who can’t qualify on their own may be eligible for the SBA Surety Bond Guarantee Program. The SBA guarantees a portion of the surety’s risk, making it easier for the surety to approve contractors who would otherwise be declined. The program covers contracts up to $9 million for non-federal projects and up to $14 million for federal projects. Contractors pay the SBA a fee of 0.6 percent of the contract price on top of the surety’s regular premium.8U.S. Small Business Administration – SBA. Surety Bonds For a contractor caught between needing bonded projects to build a track record and needing a track record to get bonded, this program is often the way through.
What Happens When a Claim Is Filed
A claim starts with formal written notice to the surety and the contractor. The notice has to lay out a specific breach, not general dissatisfaction. The surety investigates to determine whether a legitimate default has occurred under the contract, which can take weeks or months. If a default is confirmed, the surety generally has several options: assist the original contractor in finishing, take over and hire a completion contractor, pay the owner’s actual damages up to the penal sum, or deny the claim if the allegations are unfounded. The surety’s goal is to resolve the situation at the lowest cost, which often means financing the original contractor rather than switching horses.
Whatever the surety spends, the General Indemnity Agreement means the contractor and the personal indemnitors owe it back. A paid bond claim doesn’t just end the project relationship. It can also make the contractor effectively unbondable on future work, which on public projects closes off a large share of the market.