FL H1139

Defines "plan-based methodology" as requiring localized data to project 10-year growth, anticipate capacity impacts, and establish capital project lists for impact fee studies

Requires counties and municipalities charging transportation capacity impact fees to execute interlocal agreements by October 1, 2025; developers receive 10% fee reduction if no agreement exists

Limits impact fee increases beyond standard phase-in caps to 100% maximum over 4 years, requires unanimous governing body vote, demonstrated-need study within 12 months, and at least two public workshops

Prohibits governments from using data older than 4 years to justify extraordinary circumstances for exceeding phase-in limitations, and bars including deductions from previous impact fees in new increases

Entitles prevailing petitioners in impact fee challenges to refunds with interest within 90 days, plus reasonable attorney fees and costs for residents and business owners in the imposing jurisdiction