Tax bills were mailed on December 10, 2010. Holiday Hours: City Hall will be closed on Friday, December 24 and Monday, December 27. The Treasurer’s Office will be open 8 a.m. – 5 p.m. on Friday, December 31. Tax bill information will be available on the Waukesha County website beginning on Wednesday, December, 22. The Waukesha County website is www.waukeshacounty.gov. For more information on hours, locations to make payments and payment options, please call (262)787-3513 or go to our General Tax Information page.