Bond insurance is a guarantee that someone else’s promise will be kept, and if it isn’t, a third party pays. The term actually covers two different products. Municipal bond insurance is a policy a government issuer buys from a private insurer so that bondholders still get paid if the issuer defaults on interest or principal. Surety bonds are guarantees that a contractor, licensed business, or court-appointed fiduciary will perform as required, with a surety company standing behind that promise. Both shift risk away from the party relying on someone else’s performance, but they work in very different ways and show up in very different places.
Municipal Bond Insurance in Brief
When a city, county, or state agency issues bonds to finance infrastructure, it can buy a policy from a private insurer that guarantees the scheduled interest and principal payments to bondholders. If the issuer defaults, the insurer pays. The practical effect is that the bond carries the insurer’s credit rating rather than the issuer’s, which usually lowers the municipality’s borrowing costs and gives investors an added layer of protection. Companies like Assured Guaranty and Build America Mutual are among the major providers of this product.
Municipal bond insurance is a financial guarantee sold to issuers and felt by investors. It is not something a contractor, small business owner, or executor of an estate will ever buy. Those readers are looking at the second product, and the rest of this article covers it.
How a Surety Bond Works
A surety bond involves three parties, not two. The principal is the party obligated to perform: build the project, follow the licensing rules, manage the estate honestly. The obligee is the party the promise runs to, often a government agency, a project owner, or a court. The surety company is the guarantor that stands behind the principal. If the principal falls short, the obligee files a claim against the bond, and the surety investigates and pays if the claim is valid.
Here is where surety bonds part company with traditional insurance. In ordinary insurance, the insurer absorbs the loss it pays out. In surety, the surety expects to be reimbursed by the principal for anything it pays, plus legal fees and related costs. That expectation is formalized in an indemnity agreement the principal signs before the bond is issued, and it typically binds not just the business entity but the individual owners who personally guarantee the obligation.1National Association of Surety Bond Producers. Legal Spotlight: Help Contractor Clients Understand Surety’s General Indemnity Agreement A surety bond is really a credit product in insurance clothing.
What a Surety Bond Costs
Premiums generally run from about 1% to 15% of the bond amount. Where a specific principal lands depends on financial strength, credit history, business track record, and available liquidity. A well-capitalized contractor with a clean history pays toward the low end. A newer business or one with credit problems pays significantly more, and higher-risk principals may also have to post collateral. Sureties accept a narrow range of collateral: cash and irrevocable letters of credit are standard, while certificates of deposit and physical property usually are not.
The Main Types of Surety Bonds
Surety bonds divide into two broad categories. Contract bonds guarantee that specific contractual obligations, usually on construction projects, will be met. Commercial bonds guarantee that a business or individual will comply with laws and regulations in a licensed industry.2U.S. Small Business Administration. Surety Bonds Contract bonds typically involve an in-depth financial review, including audited financial statements. Commercial bonds are often simpler, with smaller ones sometimes issued on a credit check alone.
Performance and Payment Bonds
A performance bond guarantees the contractor will complete the project according to the contract. If the contractor defaults, the surety can arrange for the original contractor to finish, hire a replacement, or compensate the owner in cash.3Associated General Contractors of America. The Contract Surety Bond Claims Process A payment bond guarantees that subcontractors, suppliers, and laborers get paid. That matters most on public projects, where workers cannot file mechanics’ liens against government property to secure payment. Public construction contracts almost always require both bonds together.4AIA Contract Documents. Instructions: A312-2010, Performance Bond and Payment Bond
Bid Bonds
A bid bond assures the project owner that the contractor’s bid is serious and that the contractor can obtain the required performance and payment bonds if selected. Bid bonds are typically set at 5%, 10%, or 20% of the bid. If a winning contractor backs out or cannot secure the required bonding, the surety pays the difference between that bid and the next lowest responsive bid, up to the bond’s limit.5eCFR. 13 CFR 115.16 – Determination of Surety’s Loss
License and Permit Bonds
Many states require professionals to post a bond before they can obtain a license or permit. Mortgage brokers, auto dealers, contractors, and freight brokers are common examples. These commercial bonds guarantee the bonded party will follow applicable laws and industry regulations. A consumer or business harmed by a violation can file a claim against the bond to recover financial losses.
Fiduciary Bonds
Courts often require fiduciary bonds from individuals appointed to manage someone else’s money or property, including executors of estates, guardians of minors, and trustees. The bond protects beneficiaries against mismanagement or theft. The Department of Veterans Affairs, for example, requires corporate surety bonds in most cases where an individual is appointed as a court fiduciary for a veteran’s estate.6eCFR. 38 CFR 14.709 – Surety Bonds; Court-Appointed Fiduciary
When Bonds Are Legally Required
The Miller Act requires performance and payment bonds on federal construction contracts exceeding $150,000. It protects the government and the workers on federal projects by making sure the job gets done and everyone in the payment chain gets paid. The Federal Acquisition Regulation implements these requirements, and contracting officers cannot require a bid guarantee unless a performance or payment bond is also required.7Acquisition.GOV. FAR Subpart 28.1 – Bonds and Other Financial Protections
Most states have their own versions, commonly called Little Miller Acts, that impose similar bonding requirements on state-funded construction. Thresholds and specific rules vary by state. Beyond construction, many jurisdictions require bonds in public contracting and financial services, and failing to obtain a required bond can trigger fines, license revocation, or exclusion from bidding.2U.S. Small Business Administration. Surety Bonds
If You Can’t Qualify for a Bond
Small and emerging businesses often struggle to qualify because they lack the financial history or capital sureties want to see. The SBA’s Surety Bond Guarantee Program addresses this by guaranteeing a portion of the surety’s loss if a bonded contractor defaults, which encourages surety companies to write bonds for businesses they would otherwise turn away.2U.S. Small Business Administration. Surety Bonds The program guarantees contract bonds only, not commercial bonds. It runs through participating surety companies, and businesses have to meet SBA size standards. The SBA periodically updates the program’s standard operating procedures, including citizenship requirements for business owners, most recently effective April 2026.8U.S. Small Business Administration. Surety Bond Guarantee Program: Update to SOP 50 45 4 – Citizenship Requirements and Rescission of Policy Notice 5000-866697
Filing a Claim Against a Bond
An obligee who believes the bonded party has failed to perform starts by notifying the surety in writing. The notice should describe the alleged default and include supporting documentation: the underlying contract, records of nonperformance, payment records, and relevant correspondence. Timing is critical. Many bonds and state statutes impose deadlines for sending notices and filing claims, and missing those windows can kill an otherwise valid claim.3Associated General Contractors of America. The Contract Surety Bond Claims Process
The surety does not simply write a check. It investigates, reviews the documentation, talks to the parties involved, and decides whether the principal actually defaulted. Sureties often try to resolve the situation first by pushing the principal to cure the problem or negotiating a settlement. If the claim is valid and the default cannot be cured, the surety may pay the obligee, hire a replacement contractor, or take other steps set out in the bond. Whatever it pays, it then pursues the principal for reimbursement under the indemnity agreement.
What a Bond Will Not Cover
Every bond has a penal sum, the maximum dollar amount the surety can be required to pay. For performance and payment bonds, the penal sum is usually 100% of the contract price. For bid bonds, it is a percentage of the bid. If actual damages exceed the penal sum, the obligee has to pursue the principal directly for the rest.5eCFR. 13 CFR 115.16 – Determination of Surety’s Loss
Coverage applies only to the specific obligations the bond describes. A performance bond covers the contractor’s failure to complete the project, not the owner’s lost revenue from a delayed opening. A payment bond covers unpaid subcontractors and suppliers, not unrelated debts the contractor owes to other creditors.
Some things can void coverage entirely. If the obligee and principal substantially change the underlying contract without the surety’s consent, the surety may argue the bond no longer applies because the deal it guaranteed is not the deal that got performed. Fraud or material misrepresentation in obtaining the bond is another defense. If the principal lied about its financial condition, or the obligee misrepresented facts to induce the surety to issue the bond, the surety can seek to be released from its obligations.9International Risk Management Institute. Exoneration Based on Fraud in the Inducement as a Surety Defense
Closing Out a Bond
A surety bond does not last forever, but it does not always end on its own either. Once the principal has fully performed and any applicable warranty period has expired, the bond can be exonerated, meaning the surety is formally released from further liability. For construction bonds, this typically follows substantial completion and confirmation from the obligee that no claims are outstanding.
Principals should actively pursue formal exoneration rather than assume the bond quietly expires. That matters especially for continuous bonds, where exposure can drag on indefinitely if no one closes them out. The process generally requires written documentation from the obligee confirming that all obligations have been satisfied. A bond left open after the underlying work is done is a claim window still standing when it doesn’t need to be.