Is Kendall County, IL in a flood zone?
FEMA's National Risk Index puts Kendall County's flood hazard at the 79.7th percentile nationally — a middling flood hazard by national standards — driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 1 times a year. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Mandatory flood insurance compliance in Kendall County
Homes with a federally backed mortgage inside Kendall County's mapped high-risk flood zone (the Special Flood Hazard Area, or SFHA) are legally required to carry an NFIP flood policy. In practice, 21.6% of them do — 57 active policies against 264 structures FEMA counts in that zone, leaving a real compliance gap. Across all residential structures in Kendall County, not just the ones FEMA mandates, 0.2% carry an NFIP policy — most flood damage nationally happens outside the mapped high-risk zone, so that broader number matters too.
How Kendall County compares nationally
Kendall County sits at rank 667 of 3144 counties on FEMA's flood hazard scale (1 is worst) and rank 475 of 3144 by population (1 is biggest). About 143,171 people live in Kendall County, Illinois, spread over 320.243 square miles.
What to do next if you own or are buying in Kendall County
Across all of Kendall County's 42,416 residential structures, 101 carry an NFIP policy today — a county-wide count that still can't tell you one address's own mapped zone.
More on how this number was built
The methodology guide shows exactly which FEMA and Census tables feed Kendall County's numbers. The guide to what the Special Flood Hazard Area actually means explains why the mandatory-insurance rule exists and who it applies to.