Municipal bonds default rarely. Across the roughly $4.4 trillion muni market, investment-grade issues have a five-year cumulative default rate near 0.08 percent, according to Moody’s Investors Service, and the average annual default rate for all rated munis has hovered near 0.01 percent over more than five decades of data.1Moody’s Investors Service. Special Comment: US Municipal Bond Rating Scale So the plain answer to how often municipal bonds default is: almost never, at the investment-grade level. But the market-wide number hides big differences by bond structure and sector, and those differences are what actually determine your risk.
How Munis Compare to Corporate Bonds
Over comparable five-year windows, investment-grade corporate debt has experienced cumulative default rates many times higher than investment-grade munis. Include speculative-grade issues and the gap widens further. The structural reasons are straightforward: municipalities can tax, most states require balanced budgets, and the services munis fund tend to be essential rather than optional.
Standard & Poor’s data lines up with Moody’s. Most municipal defaults come from unrated bonds or speculative-grade issues. For bonds rated BBB or higher, the probability of a missed payment within ten years is under 0.1 percent. In dollar terms, total municipal defaults ran about $2.0 billion in 2023 and $2.1 billion in 2024 — small numbers next to the size of the market.2SIFMA. US Municipal Bonds Statistics
Default Rates by Bond Structure
The legal structure behind a bond is the single biggest driver of default risk. Two bonds from the same city can carry very different odds of missing a payment.
General Obligation Bonds
General obligation (GO) bonds are backed by the issuer’s full taxing power. Among investment-grade issuers, defaults are close to zero. GO bonds accounted for roughly 25 percent of all rated municipal defaults over the 1970–2022 period, despite representing a large share of outstanding debt.
Within GO debt, the fine print matters. Unlimited-tax GO bonds let the issuer raise property taxes as high as needed to service the debt. Limited-tax GO bonds cap the levy, which restricts the issuer’s ability to raise cash in a crisis. In Detroit’s 2013 bankruptcy, unlimited-tax GO holders recovered about 73 percent of par while limited-tax holders recovered only about 42 percent.3SEC.gov. Municipal Bonds: Understanding Credit Risk
Revenue Bonds
Revenue bonds are paid only from the income of a specific project or system — a toll road, an airport, a water utility. If that revenue falls short, holders have no claim on the issuer’s taxing power. Revenue-backed debt accounts for roughly 75 percent of all rated municipal defaults over multi-decade tracking periods.
Most revenue bond agreements include protective covenants. A typical one is a debt-service coverage ratio requiring the issuer to bring in revenue equal to something like 1.2 times annual debt service or more. Falling below the ratio can force the issuer to raise rates or take other action before an actual payment default occurs.
Conduit Bonds
Conduit bonds are the highest-risk corner of the rated market. A municipality issues the debt on behalf of a private borrower — a hospital system, a university, a housing developer, an industrial project — but the municipality has no obligation to repay. Accounting standards keep conduit debt off the issuer’s balance sheet.4Governmental Accounting Standards Board. Summary of Statement No. 91
Research covering defaults from 1999 to 2010 found conduit bonds accounted for roughly 59 percent of all defaulted municipal bond deals, while direct GO bonds made up only about 4 percent. If a muni yield looks unusually high, check whether it is a conduit issue. The municipality’s name on the bond does not put its credit behind the payments.
Lease-Backed Bonds
Certificates of participation and other lease-backed bonds depend on the governing body appropriating funds each year. If the council or legislature refuses to appropriate — a “non-appropriation” event — payments stop. Industry data shows the actual incidence of non-appropriation has been very low, averaging roughly 0.015 percent of outstanding lease obligations annually between 2008 and 2011. Fiscal distress caused about two-thirds of the reported cases in that period.
Which Sectors Default Most
Default risk clusters in specific sectors. Some run many times the market average; others almost never miss a payment.
Higher-Risk Sectors
Senior living, including nursing homes and continuing care retirement communities, carries the highest default rate in the muni market. In 2023, the sector’s default rate was 10.8 percent, against an overall municipal default rate of 0.41 percent excluding Puerto Rico. Rising labor costs and volatile occupancy have pressured operating margins.
Industrial development bonds and multifamily housing projects also default at elevated rates. Both categories are usually conduit financings tied to a single private business or developer, and if that operation struggles, bondholders have no fallback.
Smaller hospitals and other healthcare facilities face separate pressures. Medicare reimbursement changes flow directly into cash available for debt service. A Congressional Budget Office proposal to reduce Medicare’s coverage of facility bad debt, with reductions phasing in starting in 2026, is one example of how federal policy shifts can squeeze these borrowers.5Congressional Budget Office. Reduce Medicare’s Coverage of Bad Debt
Lower-Risk Sectors
Water and sewer utilities, electric systems, and primary education bonds sit at the safe end. Residents cannot easily do without these services, revenue is predictable, and rate covenants typically require the issuer to adjust fees to maintain adequate coverage. Defaults in these essential-service sectors are rare even during recessions.
Payment Default vs. Technical Default
Not every default means a missed check. The term covers two situations, and the distinction changes how you should read default statistics.
- A payment default, sometimes called a monetary default, is a missed scheduled interest or principal payment. This is the one that hits your cash flow.
- A technical default is a violation of a non-payment covenant — for example, failing to file audited financials on time, or letting a debt-service coverage ratio slip below the required level.
A Brookings Institution study of general-purpose local government defaults from 2009 to 2015 examined 415 bond deals that experienced some form of default. Of those, 52 involved only a technical default, 142 involved only a monetary default, and the rest experienced both. Technical defaults spiked in 2012, reaching 162 bonds in that single year. Technical defaults don’t directly cost bondholders money, but they often precede payment problems.
Under SEC Rule 15c2-12, issuers must report both payment delinquencies and material non-payment defaults through the MSRB’s EMMA system, generally within ten business days.6Municipal Securities Rulemaking Board (MSRB). Selecting Event Disclosure Categories on EMMA Dataport
What Happens When a Muni Does Default
Recovery rates on defaulted munis are considerably higher than on defaulted corporates. Moody’s data shows an average recovery of 66 percent of par for defaulted municipal bonds versus 42 percent for defaulted corporates. About 45 percent of defaulted munis recovered 75 percent or more of par, compared with 16 percent of defaulted corporates, and roughly 36 percent of defaulted munis were eventually quoted at full par value.7Moody’s Investors Service. Special Comment: US Municipal Bond Rating Scale – Section: Recovery Rates on Defaulted Bonds
The reason is structural. A company can be liquidated. A municipality keeps operating, keeps taxing, and keeps generating revenue. Federal bankruptcy law protects that: under Chapter 9, a court cannot interfere with a municipality’s governmental powers, property, or revenue-producing assets without the debtor’s consent.8Office of the Law Revision Counsel. 11 USC Ch. 9: Adjustment of Debts of a Municipality
Detroit, 2013
Detroit filed for Chapter 9 in July 2013 with roughly $18 billion in debt and unfunded liabilities, the largest municipal bankruptcy by debt volume at the time. City bondholders recovered around 64 cents on the dollar overall. The unlimited-tax versus limited-tax GO split — 73 percent versus 42 percent — showed that even “full faith and credit” bonds can take real losses, and that the specific tax pledge matters.
Puerto Rico, 2015 to 2022
Puerto Rico’s crisis was far larger. The territory declared its $70 billion in debt unpayable in 2015, Congress created the PROMESA oversight framework the following year, and the main restructuring plan took effect in March 2022, cutting total liabilities from over $70 billion to approximately $37 billion. Recoveries varied sharply by lien: senior COFINA sales-tax bondholders got roughly 93 percent, junior COFINA holders about 55 percent. Restructuring at the PREPA electric utility continued beyond the main settlement.9Puerto Rico Fiscal Oversight Board. Puerto Rico’s Debt Restructuring Process
Both cases point the same direction. Averages are useful, but the answer to how often a particular municipal bond defaults depends on what kind of bond it is, what sector it funds, and where it sits in the payment structure. At the investment-grade GO end of the market, default is a rounding error. At the conduit senior-living end, it is a real and recurring event.