Federal deferral doesn't automatically mean state deferral forever. Most states conform to Section 1031, but California famously tracks gain that leaves the state — exchange a CA property for one in Texas and you'll file Form FTB 3840 every year until you sell for cash, at which point California taxes its share, wherever you live. Several states also withhold tax at closing from out-of-state sellers unless you file the exchange exemption paperwork in advance. None of this kills exchanges; all of it punishes the unprepared.
Exchangers plan the federal deferral meticulously, then assume the state follows along quietly. Mostly, it does — nearly every state with an income tax conforms to Section 1031 for real property (Pennsylvania, the last major holdout, finally conformed for tax years beginning in 2023). The expensive surprises live in two mechanisms most first-time exchangers have never heard of: claw-backs and closing-table withholding.
Exchange a California rental into a Florida property and California's position is simple: the gain that accrued on CA soil is CA-source income, and deferral is not forgiveness. Since 2014, exchangers who swap California property for out-of-state property must file Form FTB 3840 with California every single year, reporting the deferred gain and the current status of the replacement property — a standing annual reminder that Sacramento is waiting. When you eventually sell for cash (no matter the state, no matter where you've moved), California taxes its tracked share of the gain, at rates that treat capital gains as ordinary income and currently top out above 13%.
Skip the 3840 filing and California can treat the deferral as broken — accelerating the tax. It's not an optional formality; it's the price of the deferral continuing.
The claw-back changes endgame math, not exchange math. Exchanging out of California still defers everything today. But if your long-term plan is "swap till you drop" toward a step-up at death, the tracked gain generally dies with you like the federal gain does — while a plan that ends in a cash sale is carrying a hidden double-digit California liability that most projection spreadsheets forget. A handful of other states (Massachusetts and Oregon among them) assert similar source-tracking positions. Ask about your specific state pair before you exchange, not at exit.
Separate trap, earlier in the timeline: many states require the closing agent to withhold state tax from out-of-state sellers at closing — commonly a few percent of the sale price or gain, remitted straight to the state. On a 1031, having tax withheld defeats the point (and creates instant cash-flow pain), so these states offer exchange exemption certificates or affidavits: paperwork certifying the sale is part of a 1031, filed before or at closing, that reduces or eliminates the withholding. The operative words are before closing. File late and you're chasing a refund from a state revenue department while your exchange proceeds sit short — recoverable, eventually, but a self-inflicted wound. Your QI and closing attorney handle this routinely if they know your situation early; it's a first-phone-call topic, not a closing-week one.
Nonresident filing obligations: own the replacement property in a new state and you've typically acquired an annual nonresident return there — small cost, real paperwork. Community property and title: crossing between community-property and common-law states can complicate the same-taxpayer requirement for married couples; cheap to confirm, expensive to fix. Local transfer taxes: a few high-tax cities and counties impose transfer taxes that don't care about your federal deferral — price them into the exchange budget like any closing cost.
Four questions, asked once, before day zero: Does my selling state withhold from nonresident or exchange sellers, and what's the exemption form and deadline? Does my selling state claw back gain that leaves (and what's the annual filing)? What are the ongoing filing obligations in my buying state? And does my CPA handle multi-state returns, or do I need one who does? Twenty minutes with the right professional; the alternative is starring in a future case file.
A free, no-obligation introduction to a vetted 1031 or DST partner — with our referral relationship disclosed in writing. On the 45-day clock? Same-day attention.