Sioux Falls, SD Accessory Structures: ADU Impact Fees (2026)

Unlike many western states, South Dakota does not have a general statutory impact-fee enabling statute analogous to California Government Code §66000 (Mitigation Fee Act), Washington RCW 82.02.050, or Colorado CRS §29-20-104.5. Sioux Falls accordingly does not charge a separately enumerated 'impact fee' on ADUs. Costs for an ADU instead consist of: (1) the building permit fee based on valuation per the city's Building Permit Valuation/Fee Schedule; (2) plan review fees; (3) water and sanitary sewer connection or tap fees set by Public Works under Title 170 (Utilities) if a new service is required; and (4) any electrical permit fees. ADUs that share the principal dwelling's utility service typically avoid new tap fees. Sioux Falls funds new infrastructure primarily through the 2% municipal sales tax (SDCL Chapter 10-52) and the second-penny sales tax dedicated to capital improvements, not through impact fees. Where the ADU is in the Joint Zoning area (Minnehaha or Lincoln County), county wastewater capacity proof is required (§ 159.305) but no impact fee is levied. Because there is no separate ADU surcharge, Sioux Falls is comparatively inexpensive for ADU construction relative to coastal jurisdictions.