These come from the FDA Food Code, which nearly every state adopts. A health inspector checks for them on plan review and at inspection — regardless of your state:
Also required in most kitchens: a mop/service sink (cleaning-water disposal), mechanical exhaust hood (Type I over grease/smoke), adequate hot water, indirect waste/air gaps on food & warewashing equipment, and a grease interceptor where local plumbing code requires it.
Licensing authority: WI Dept. of Agriculture, Trade & Consumer Protection (DATCP), or a local public health dept acting as DATCP agent. Regime: DATCP + 14 agent jurisdictions, licence valid STATEWIDE.
CORRECTION - a widely repeated secondary source claims Wisconsin has no reciprocity. DATCP's own site says the opposite: these licence types are transferable from one location to another, so a licence from Sheboygan County lets you operate in Marathon County without additional licensing. Public Health Madison & Dane confirms it operationally - DATCP state mobile licensed vendors are exempt from additional public health licensing, though they may still face an inspection and a $25 fee, and you must carry the DATCP licence during service or you may be required to buy a local one. If you operate ONLY in Dane County you take the local annual licence instead. Roughly 14 agent jurisdictions run their own programmes (Milwaukee, Madison/Dane, Brown, Racine, Kenosha, La Crosse, Marathon, Outagamie, Sheboygan, West Allis, Waukesha, Winnebago); DATCP licenses everywhere else. WHICH ONE licenses you is set by where your SERVICE BASE sits, not where you vend. Plan review stays with the issuing authority (DATCP $185, Milwaukee $200, Madison/Dane $250; 2-5 weeks). Annual licence roughly $250-500 by risk category; Milwaukee about $355. ATCP 75 is the state food code; ATCP 75.10 grades units Simple / Moderate / Complex by point value. Service Base licence required, 24-hour return unless exempted - ask. Unit needs commercial-grade equipment, non-hand-operated handwash with soap and single-use towels, ventilation and fire extinguishing, and an air-gapped commercial prep sink if prep happens aboard. Licence year runs 1 July - 30 June.
Mobile/food-truck reciprocity: YES - DATCP states licences are transferable between jurisdictions
New builds and remodels almost always require a plan review and a pre-opening inspection. Submit your equipment layout early — the sink count, hood, and hot-water sizing are the usual sticking points.
See restaurant-equipment dealers in Wisconsin → — many do design + fabrication and know local plan-review requirements.