Provisional. Ranked October 7, 2026 from the filings the IRS had published by then. Organizations have up to 10½ months after their year ends to file, so the list will change as the rest arrive.
| Rank | National | Organization | Growth | Revenue |
|---|---|---|---|---|
| 1 | 1 | Illuminus Retirement Communities INC Watertown, WI · Housing | 50,098% | $107K → $53.9M |
| 2 | 15 | Missionaries of the Word INC Egg Harbor, WI | 3,947% | $377K → $15.3M |
| 3 | 81 | Marathon County Historical Society Wausau, WI · Arts and culture | 1,688% | $288K → $5.2M |
| 4 | 88 | The Mooring Foundation INC Appleton, WI | 1,564% | $172K → $2.9M |
| 5 | 109 | Badgerland After School Enrichment Program INC Fort Atkinson, WI · Education | 1,313% | $354K → $5.0M |
| 6 | 177 | Wisconsin Preservation Fund INC Milwaukee, WI · Housing | 819% | $1.0M → $9.3M |
| 7 | 297 | Dane County Humane Society Madison, WI · Animals | 554% | $4.7M → $31.0M |
| 8 | 449 | Thompson Center on Lourdes INC Appleton, WI · Human services | 405% | $436K → $2.2M |
| 9 | 456 | Boys & Girls Club of Janesville INC Janesville, WI · Youth development | 401% | $1.1M → $5.6M |
| 10 | 472 | Matthias Academy Corporation Benet Lake, WI · Human services | 391% | $2.6M → $12.6M |
| 11 | 543 | ST Croix Valley Foodbank INC Hudson, WI · Food and agriculture | 352% | $1.3M → $6.1M |
| 12 | 682 | First Nations Community Financial Black River Falls, WI · Community improvement | 293% | $620K → $2.4M |
| 13 | 823 | Serenity Inns INC Milwaukee, WI · Human services | 250% | $736K → $2.6M |
| 14 | 845 | Woodland Pattern INC Milwaukee, WI · Arts and culture | 246% | $735K → $2.5M |