RealFiModel · Field Notes

The 1031 Cheat Sheet

Everything you need to defer the tax without driving the deal off a cliff. The rules are boring. The behavior they encourage is where the bodies are buried.

A 1031 exchange lets you sell an investment property, roll the whole proceeds into another like-kind real property, and defer the capital gains tax you'd otherwise owe. Not erase — defer. The IRS isn't your friend here; it's your extremely patient creditor, and it always gets paid eventually: when you finally sell for cash, or when you die without one more exchange queued up. Used on a deal you'd happily own anyway, it's a genuine wealth-builder. Used to dodge a tax bill at any cost, it's a leash that drags you into properties you'd never touch with clear eyes.

This sheet covers the actual 2026 rules — the clocks, the identification options, the equal-or-up math, the intermediary you can't skip — plus the traps that quietly turn a "tax-free" swap into a taxable one. Keep it next to the model, not in place of it. Because the exchange will defer your gain into a brilliant acquisition and a catastrophic one with exactly the same enthusiasm. Knowing the rules is step one. Underwriting the deal is the step nobody can do for you.

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Defer ≠ erase. Every time you "skip" the tax, you're not avoiding the monster — you're feeding it and giving it a bigger room.

The Rule

What qualifies

Real property held for investment or business use, swapped for like-kind real property. The "like-kind" bar is broad: an apartment building for raw land, one rental for a portfolio, a warehouse for retail.

Does NOT qualify: your home, a personal-use vacation place, or a fix-and-flip held for resale. Since 2018, personal property (equipment, vehicles) is out entirely — real estate only.

The real tax bill

When you finally pay, it's not just capital gains. It's gains plus depreciation recapture (higher rate) plus the 3.8% NIIT for high earners plus your state's cut.

Stacked, that commonly lands at 30–40% of the gain. That's the monster the deferral keeps in the closet.

Swap till you drop

Chain exchanges indefinitely and you keep deferring. Die still holding, and under current law heirs get a stepped-up basis — the deferred gains can evaporate.

Great for patient people who own things they understand. Dangerous when the tax tail starts wagging the deal.

You don't get 225 days. You get 180 total. The 45-day and 180-day clocks run at the SAME time, from the same Day Zero. People lose entire deals over this math.

The Clocks

▶

Day 0 — the sale closes

Both clocks start the day your relinquished property closes and the QI takes the proceeds. Not the day you list. Not the day you go under contract. Closing.

Identify by Day 45

Identify replacement property in writing, signed, delivered to your QI (not your agent) by Day 45. No extensions for weekends, holidays, or anything else.

180

Close by Day 180 — or sooner

Acquire the replacement by the earlier of 180 days or your tax-return due date. Sell late in the year? File an extension or your window gets amputated.

Pick Your Identification Rule (by Day 45)

3-Property Rule

Name up to three properties, any value. The default for most investors. Pro tip: use all three slots even if you're sure — your sure thing can fall through.

200% Rule

Name any number of properties, as long as their combined value is ≤ 200% of what you sold.

95% Rule

Name unlimited properties of any value — but you must actually close on 95% of that identified value. For people who enjoy living dangerously.

Trade equal-or-UP on price AND debt — or you create "boot," and boot is taxable. Buy cheaper, pocket cash, or carry less leverage, and you just taxed yourself in a "tax-free" deal.

The Non-Negotiables

Hire a Qualified Intermediary first

The exchange agreement must be in place before you close the sale. You may never touch the proceeds — one minute in your account kills the whole exchange.

Disqualified persons (can't be your QI): your CPA, attorney, real estate agent, broker, employee — anyone who's been your agent in the past two years — or your relatives.

8824

Report it on Form 8824

Filed with the return for the year you sold (not the year you bought), even if the deal straddles two calendar years.

Numbers must match your closing statements exactly — mismatches are a classic audit trigger.

Equal-or-up, in plain math

Replacement price ≥ net sale price of what you sold, and replace the debt you paid off.

Trade up = full deferral Trade down = taxable boot

A low cap rate three states from home isn't a feature — it's a warning label. You're paying full price today for growth that has to show up tomorrow, in a market you don't know, on a broker's word.

Where It Goes Off The Rails

The traps that tax you

Missing Day 45 — the most common failure. No grace period. Exchange dies.
Touching the proceeds — even briefly. Instant disqualification.
Trading down on price or debt — creates taxable boot.
Disqualified QI — using your own agent/CPA/attorney.
Q4 timing — tax-return due date quietly shortens your 180 days.

The state clawback

Exchange a gain out of a high-tax state (California is the famous one — Form FTB 3840) and the state still considers that deferred gain theirs.

You file an annual return tracking it indefinitely, so they can collect when you finally cash out. You moved the building. You didn't move the tax.

EGO

The behavioral trap

Three wins in a row and you stop underwriting deals — you start underwriting your streak.

The fix is unglamorous: model the worst case before the best one, every time, win or lose. Let the numbers lead, not the ego.

The person selling you the assumptions never pays for them being wrong. The broker gets paid at closing. You get paid only if the pro forma was true. Verify every number yourself.

Bottom line: a 1031 is a tool, not a cheat code. It defers tax — it does not make a bad deal good, underwrite your property, or save you from leverage and optimism. Use it on a deal you'd own even if the exchange didn't exist. Stress-test the downside, keep your deferred liability (including any out-of-state clawback) visible on the books, and stay in the markets where your knowledge is a real edge. Model it before you commit at RealFiModel.com.

Not tax or investment advice. 1031 exchanges carry strict, unforgiving deadlines and disqualification rules. Work with a Qualified Intermediary and a CPA before acting on anything here. Rules current as of 2026 and subject to change — yes, everyone disclaims; now you know why.