State Tax Forms

State taxes for businesses that touch more than one state

Tax laws vary state to state. What you owe and the forms you file depend on where you live, where you work, where your business operates, and sometimes where your customers are. For a small business that ships into multiple states, has employees in two states, or simply has an owner who relocated mid-year, the answer to “what do I owe and where do I file?” is rarely simple. The links below point to each state's current-year form library — your starting point for preparing any state return.

Three patterns trip up most Florida-based business owners. First, nexus — the legal standard for owing tax in a state. Since the 2018 Wayfair decision, economic nexus thresholds (often $100K in sales or 200 transactions) trigger sales-tax registration even with no physical presence in the state. Second, employee state-tax withholding — if your bookkeeper, remote sales rep, or contractor lives outside Florida, you may owe withholding registration there. Third, apportionment for multi-state corporate income — most states use a three-factor (sales, payroll, property) or single-sales-factor formula to decide what slice of your income they tax. The forms in those states change every year; the rules change every couple.

SMAART's state & local tax (SALT) team handles multi-state nexus reviews, voluntary disclosure agreements when you discover you should've been filing in a state for years, and apportionment math on corporate returns. The form directory below is for the do-it-yourself starting point — book a consult if you want us to run the actual filing.