The 1031 Exchange Clock
Enter your closing date. Get the two dates that decide whether your exchange survives — plus the third deadline most investors never hear about until it has already passed.
The 45-day and 180-day deadlines run on calendar days and do not move for weekends or holidays. Miss either one by a day and the exchange fails — the entire gain becomes taxable in the year you sold. This calculator computes both, checks them against your tax return due date, and gives you a dated checklist you can print and hand to your attorney.
What you're allowed to identify
By midnight on Day 45 you must deliver a signed, written identification to your qualified intermediary. You get one of three rules — you don't get to mix them, and you can't change the list after Day 45.
Will you actually defer everything?
Hitting the dates is necessary but not sufficient. To defer the full gain you have to buy up in price, reinvest all the equity, and replace the debt you paid off. Anything left over is boot, and boot is taxable now. Fill in what you know — leave the rest blank.
Your dated checklist
Every item carries the actual date it's due for your transaction. Tick them off — the boxes hold while you're on the page. Print this and give a copy to your closing attorney and your CPA.
Deadline math. IRC §1031(a)(3) and Treas. Reg. §1.1031(k)-1(b). Day 1 is the day after the transfer of the relinquished property. The 45-day and 180-day periods run on calendar days and are not extended when they land on a Saturday, Sunday, or federal holiday — the weekend rule of IRC §7503 does not apply to them. The tax return due date is subject to that rule, so we shift it to the next business day and account for D.C. Emancipation Day.
The 180-day cap. The exchange period ends on the earlier of 180 days or the due date, including extensions, of your return for the tax year in which the transfer occurred. We use standard calendar-year due dates. Fiscal-year filers and short tax years should use the manual override.
Disaster relief. Rev. Proc. 2018-58 §17 lets the IRS extend both deadlines, usually by 120 days, for taxpayers affected by a federally declared disaster. This tool does not check for active relief notices. If a disaster has been declared where you or the property sits, check IRS newsroom guidance before assuming the dates below.
Rhode Island withholding. R.I. Gen. Laws §44-30-71.3 and 280-RICR-20-10-1. Nonresident sellers face withholding of 6% for individuals, estates, partnerships, and trusts. The current regulation states 7% for nonresident corporations; some older Division of Taxation materials still show 9%. Confirm the rate in force with your closing attorney. The Form RI 71.3 Election must reach the Division of Taxation at least 20 days before closing, and it is required even when a 1031 exchange means nothing will be withheld.
Connecticut. Connecticut conforms to federal §1031 treatment, so a properly structured exchange defers Connecticut income tax on the gain along with the federal tax. We have found no Connecticut Department of Revenue Services regime requiring withholding at closing from nonresident real property sellers comparable to Rhode Island's, and this tool does not assert one; a handful of qualified-intermediary marketing sites describe such a requirement and we could not corroborate it against a state source. Ask your closing attorney rather than relying on either claim. What is certain: Connecticut's real estate conveyance tax is not waived for like-kind exchanges. It is due on the full consideration at the relinquished closing, and it reduces the proceeds you have available to reinvest.
The boot estimate. Simplified. It applies unrecaptured §1250 gain at 25% before long-term capital gain rates, and it does not model suspended passive losses, partial-year depreciation, installment treatment, related-party rules under §1031(f), state add-backs, or the interaction with your other income. Treat the number as an order of magnitude that tells you whether to call your CPA today or next week — not as a return.
This is not tax or legal advice. Seaport Real Estate Services is a brokerage and appraisal firm. We are not attorneys, CPAs, or qualified intermediaries, and we do not hold exchange funds. Every exchange should be reviewed by your own tax counsel before the relinquished property closes.