The City of Newcastle contracts its municipal court services with the City of Mercer Island. All court proceedings, including traffic and criminal matters, are handled by the Mercer Island Municipal Court.

Mercer Island Municipal Court hears all criminal misdemeanor cases and processes all non-criminal traffic citations and parking citations for violations occurring within the city limits of Mercer Island and Newcastle.

Mercer Island Municipal Court is now located in Newcastle City Hall

12835 Newcastle Way, Suite 301
Newcastle, WA 98056
Phone: 206.275.7604
Email: court@mercerisland.gov
Fax: 206.275.7980

*** All hearings will be held on Floor 2 – Newcastle City Council Chambers ***

Mailing Address

Mercer Island Municipal Court
12835 Newcastle Way, Suite 301
Newcastle, WA 98056

Hours of Operation

Monday – Thursday: 9:00 am to 4:00 pm.
If the front door is locked during hours of operation, please call 206-275-7604, option 4 The court is closed on Fridays, Saturdays, Sundays, and Holidays.

Mercer Island Municipal Court does not handle civil protection orders or civil or small claim cases.