California & Illinois: A Tale of Two Municipal Bond Markets
California and Illinois anchor the two ends of the U.S. muni credit spectrum. Understanding both is a masterclass in how state fiscal management shapes bond value.
The California and Illinois municipal bond markets sit at almost opposite ends of the U.S. state credit spectrum. California, home to more than $100 billion of outstanding state general obligation debt, has ratcheted its rating up over the past decade to AA/Aa2, backed by a diversified $3.9 trillion economy, an aggressive rainy-day fund and a technology-heavy tax base. Illinois, with roughly $30 billion of state GO debt, has clawed its way back from a near-junk trough to a low investment-grade A/A3 rating, still weighed down by nation-leading pension liabilities and a structural budget imbalance.
For a muni investor, understanding these two markets is a compressed education in how state fiscal management, economic structure and political dynamics translate into bond yields, spreads and credit trajectories. This piece works through both markets — economy, budget, pensions, sectors, and current relative value.
California: the economy is the credit
California's credit story is dominated by its economy. The state generates roughly 14% of U.S. GDP, hosts the largest concentration of Fortune 500 headquarters in the country, and captures an outsized share of national capital gains tax revenue in strong equity market years. That revenue mix is a double-edged sword: in booms, California runs multi-billion-dollar surpluses; in busts, its top-heavy income tax collapses. The state has responded by building the Rainy Day Fund to over $22 billion, providing a genuine buffer against the next downturn.
California sectors worth watching
Beyond the state GO, California's muni market is huge and varied. Los Angeles Department of Water and Power (AA rated), San Francisco International Airport (A), Bay Area Rapid Transit (AA), and the University of California system (AA) are the household-name credits. Water and sewer bonds from the largest districts — Metropolitan Water District of Southern California, East Bay Municipal Utility District — trade at historically tight spreads and are staples of in-state portfolios.
| Issuer | Rating | 10-yr yield |
|---|---|---|
| State of California GO | AA/Aa2 | 3.45% |
| LADWP Water | AA/Aa2 | 3.35% |
| Bay Area Toll Authority | AA/Aa2 | 3.55% |
| Metropolitan Water | AAA/Aa1 | 3.20% |
Whether you're buying California or Illinois paper, the same credit analysis discipline applies — our guide to understanding municipal bond credit ratings explains how to read agency reports, interpret pension funding ratios and set up EMMA alerts on every CUSIP you own.
Illinois: the pension shadow
Illinois is a fundamentally different credit. The state carries roughly $140 billion in unfunded pension liabilities across its five systems, giving it the worst funded ratio of any U.S. state — under 45%. Every budget starts with a legally required, ever-rising pension contribution that consumes a growing share of general revenues. The state has made real progress since its 2017 rating trough — passing on-time budgets, building a modest rainy-day fund from cannabis and gaming revenue, and paying down its backlog of unpaid bills — but the fundamental fiscal math remains challenging.
"Illinois is the muni market's ongoing case study in how far a state can lean into pension underfunding before markets and rating agencies force a change. That the state trades where it does today is a testament to both the muni market's forgiveness and the durability of state-level general obligation pledges."
— Illinois credit note, 2026 investor letter
Chicago and its overlapping units
Chicago itself is a distinct credit story. The city carries a lower rating than the state (BBB+/Baa1) due to its own pension challenges, but has built impressive fiscal reforms since 2019 — casino revenue, TIF reform, and a growing property tax base. The bigger challenge is the overlapping units: Chicago Public Schools (BB+), Cook County (AA-), and the various sister agencies. Careful investors read every layer of the tax burden before pricing any Chicago-area credit.
Relative value in 2026
Through the first half of 2026, active muni managers have generally overweighted essential-service California revenue bonds (water, sewer, transit) as spread-tight but credit-defensive, and modestly overweighted Illinois state and select Chicago-area credits for the yield pickup. Neither state is a monolithic call; both offer rich menus of individual credits at different risk-reward points. The clearest lesson from watching both is the same lesson that runs through the whole muni market — the rating letter is a starting point, not an ending point.
Questions readers ask about this topic
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