Photo: Corey Coyle · CC BY 3.0Living in Windsor, WI: what to set up and who to call
Windsor Water Utility South has a clean five-year EPA record, but its latest lead result, 5.5 ppb, was higher than 93% of similar systems’ (the action level is 15). Elections in Windsor are run by Windsor itself; register with the Village of Windsor Clerk.
I’m new in town
What to set up in Windsor, and who provides it. Tap an answer for the details and where they come from.
Power, water and internet
Who to call to start service at a new address in Windsor.
Power comes from Wisconsin Power & Light
Wisconsin Power & Light (Wisconsin Power & Light Co), an investor-owned utility, serves all of Windsor. Its homes paid an average of 18.5¢ per kWh in 2025, about $128 a month (its average across Wisconsin).
Service territory: HIFLD Electric Retail Service Territories (map dated Aug 2023). Prices and customers: EIA-861, 2025.
Water comes from Windsor Water Utility South
Windsor Water Utility South supplies Windsor: about 37% of residents live in its service area. Deforest Waterworks serves another 22%. About 40% of homes are outside any mapped community water system, most likely on private wells, which EPA doesn’t regulate. It draws ground water and serves 4,607 people in all.
No health-based violations reported to EPA in the five years to October 2026, like 80% of the 5,012 systems serving 3,301–10,000 people.
The latest lead result on file, the 90th percentile of homes sampled in Jun–Sep 2023, was 5.5 ppb, below the 15 ppb action level that applied. That’s higher than 93% of similar systems’ latest results.
The system’s full record: EPA ECHO report
EPA SDWIS via Envirofacts (violations pulled Oct 9, 2026) and ECHO (lead samples, 2026Q3); service area: EPA Community Water System Service Area Boundaries v3.0 (EPA’s estimate). Violations are counted by the start of their compliance period. WI1130267.
9 home internet providers serve Windsor
97% of 3,038 addresses can get 100/20 Mbps; 83% can get fiber.
| Provider | Technology | Addresses | Fastest (Mbps) |
|---|---|---|---|
| Spectrum | Cable, Fiber | 90% | 1,000/35 |
| TDS Telecom | Fiber | 79% | 1,000/1,000 |
| UpNetWI | Fixed wireless, Fiber | 33% | 60/20 |
| AT&T | Fixed wireless, DSL | 30% | 25/3 |
| Brightspeed | DSL, Fiber, Fixed wireless | 18% | 940/940 |
| T-Mobile | Fixed wireless | 86% | 100/20 |
FCC National Broadband Map, as of December 2025. Availability as providers report it, not speeds people get.
We don’t have Windsor’s trash rules yet
Pickup rules, the dump and recycling in Windsor.
Where your child goes to school
Public school districts and the school path by grade.
Most of Windsor (99%) is in DeForest Area School District.
B+School gradeSee Schools →U.S. Department of Education, NCES Common Core of Data, 2024–25. Enrollment rules and registration are the district’s.
Town hall and registering to vote
Who to call, and how to register.
Election office: FVAP local election office directory, updated May 2026; jurisdictions: EAC EAVS 2024. Registration rules and links: vote.gov, updated Nov 18, 2024.
Windsor spans 4 ZIP codes
ZIP codes where Windsor residents live, with the share of the town in each.
| ZIP | Post office name | Share of Windsor | ZIP’s residents in Windsor |
|---|---|---|---|
| 53598 | Windsor, WI | 46% | 100% |
| 53532 | Deforest, WI | 42% | 23% |
| 53590 | Sun Prairie, WI | 8% | 2% |
| 53571 | Morrisonville, WI | 4% | 100% |
Census 2020 ZIP Code Tabulation Areas, by census block; post office names: GeoNames (CC BY 4.0). ZIPs created since 2020 are missing.
Getting around, the ER and the library
One line each; the subject pages have the rest.
ER: CMS hospital data. Library: IMLS Public Libraries Survey, FY2024.
Questions about living in Windsor
Who supplies Windsor’s drinking water, and has it had violations?
Windsor Water Utility South (EPA ID WI1130267). It reported no health-based violations to EPA in the five years to October 2026; 80% of systems its size had none. Its latest lead 90th percentile was 5.5 ppb (Jun–Sep 2023), against a 15 ppb action level.
Who provides electricity in Windsor?
Wisconsin Power & Light (Wisconsin Power & Light Co), an investor-owned utility. Its homes paid about 18.5¢ per kWh in 2025 (EIA).
What internet providers serve Windsor?
Spectrum, TDS Telecom, UpNetWI, AT&T, Brightspeed, T-Mobile (FCC, as of December 2025).
What ZIP codes are in Windsor?
53598 (46%), 53532 (42%), 53590 (8%), 53571 (4%), by share of residents. Census 2020 ZIP Code Tabulation Areas.
What school district is Windsor in?
DeForest Area School District.
How do I register to vote in Windsor?
In Wisconsin you can register online until 20 days before Election Day, in person up to and including Election Day, or by mail (postmarked 20 days before). Elections here are run by the Village of Windsor Clerk. Check your registration at myvote.wi.gov.
Sources & dates
Every answer above names its source. Here they are with their dates.
- Water: EPA SDWIS (Envirofacts, pulled Oct 9, 2026), ECHO SDWA 2026Q3, EPA CWS Service Area Boundaries v3.0.
- Power: HIFLD Electric Retail Service Territories (map Aug 2023); EIA-861 final 2025.
- Trash: OpenStreetMap, Geofabrik extract of Oct 9, 2026. © OpenStreetMap contributors (ODbL).
- ZIP codes: Census 2020 ZCTA relationship files; GeoNames postal codes (CC BY 4.0).
- Schools: NCES Common Core of Data, 2024–25.
- Registration: vote.gov, updated Nov 18, 2024 (read Oct 10, 2026). Official sites and area codes: Wikidata.
- Election office: FVAP local election office directory (fetched Oct 10, 2026; each record dated), EAC EAVS 2024 jurisdictions; registration and lookup links from vote.gov’s state data, checked Oct 10, 2026.
- Internet: FCC National Broadband Map, as of December 2025.