Quiet Hours: Downers Grove vs Naperville

When did DuPage County's residential noise ordinance take effect?

The DuPage County Board approved ordinance JPS-O-0001-25 on April 22, 2025, amending Chapter 26, Article IV, Section 26-10-15 of the County Code to address "loud and raucous" amplified noise. Before this amendment, the section only reached industrial-type noise, so late-night amplified parties in unincorporated areas could not be cited.

Does the DuPage County noise ordinance apply inside Naperville or Wheaton?

No. The DuPage County noise ordinance applies only in UNINCORPORATED DuPage. Inside incorporated municipalities — Naperville, Wheaton, Downers Grove, Lombard, Addison, and so on — the city or village noise ordinance applies and the local police department handles enforcement.

Are schools, parks, and colleges exempt from the county noise ordinance?

Yes, partially. The ordinance exempts "sounds originating from the normal and intended use of the recreational facilities of schools, colleges and public parks between the hours of 9 AM and 11 PM." Outside those hours, or for non-recreational uses, the loud-and-raucous noise prohibition still applies.

Who do I call to report a loud party in unincorporated DuPage County?

Call the DuPage County Sheriff's Department at (630) 407-2400. The 2025 amendment to Section 26-10-15 specifically empowers deputies to issue a citation for amplified noise in unincorporated areas. For incorporated cities and villages, call the local police department instead.

What are Naperville's quiet hours?

Quiet hours run from 7 PM to 7 AM. During these hours, stricter decibel limits apply to all zones, with residential areas having the lowest thresholds.

How is noise measured in Naperville?

Noise is measured at the property line of the parcel generating the sound using a sound level meter conforming to ANSI S1.4-1983 specifications.