Here's a trade I made early on. I sold one single-family rental that was cash flowing $580 a month, and rolled it into five new units that together cash flow $1,983 a month. I didn't come up with a dollar of new out-of-pocket money to do it, and I didn't pay a cent of capital gains tax on the sale.
That's a 1031 exchange, and once you understand it, the way you think about your equity changes completely.
Quick disclaimer up front: I'm an investor sharing what's worked for me, not a CPA. Tax rules are specific and the stakes are high, so run any exchange through your own CPA and a qualified intermediary.
What a 1031 exchange actually is
A 1031 exchange takes its name from Section 1031 of the IRS tax code. In plain terms: you sell an investment property, reinvest the proceeds into another investment property, and defer the capital gains tax you'd otherwise owe.
The key word is defer. You're not erasing the tax, you're pushing it down the road. And because you can keep doing exchanges, deal after deal, many investors defer that gain indefinitely. It's one of the best benefits of owning real estate, and a strategy every investor with appreciated property should at least understand.
A few foundational facts:
- You can exchange any investment property for any investment property. Single-family into multifamily is completely allowed, which is exactly how I've used it to trade up.
- You must use a qualified intermediary, a tax-deferred exchange specialist who receives the sale proceeds and passes them to the next property. You cannot touch the money yourself, ever, or the exchange is blown.
- The funds can only be used for acquisition costs, not repairs.
- Fees run roughly $1,500 to $6,000 depending on the exchange type.
The two deadlines that rule everything
This is where 1031s get stressful, so know the clock cold. Both deadlines run from the day you close the sale of your old property:
- 45 days to identify your potential replacement properties, in writing.
- 180 days to close on the replacement.
These are strict and generally immovable. The forced timeline is the single biggest drawback of a 1031, and it's why I always line up my replacement before I'm under the gun. In one of my exchanges, I was in Costa Rica on the final day of my 45-day window when a backup deal fell through, and I had to identify a replacement that same day. It worked out, but I don't recommend cutting it that close.
The boot rule
You don't have to roll 100% of your profit into the exchange. You choose how much. But anything you keep, called boot, is taxable.
Say you have $200,000 in gains. Reinvest $150,000 and pocket $50,000, and that's fine, but you'll pay tax on the $50,000 you kept. This is useful flexibility: sometimes you want some cash out and you're happy to pay tax on just that portion.
What it looks like in practice
Let me walk through two real exchanges.
One home into five units. I owned a detached condo I'd bought at a foreclosure auction in 2012. The tenants stayed five years without a single maintenance call. When they finally moved out, I did a full remodel, about $8,000 over three weeks: new cabinets, flooring, paint, fixtures, doors, and landscaping. I listed it, got multiple offers, and accepted one $15,000 over asking. Before listing, I'd already made offers on a triplex in Tennessee and a duplex in Washington, both contingent on my sale closing, so I'd never be scrambling for replacements. The result: I traded one home cash flowing $580 a month into five units cash flowing $1,983, with no new out-of-pocket cash.
A duplex into ten units. Later I sold a duplex we'd built in Everett that had about $220,000 in equity and cash flowed roughly $900 a month. The rents were $2,400 a side, and I worried that wasn't recession-proof. We sold it for $670,000 and 1031'd into an eight-unit and a duplex in Tennessee, taking gross rents from $4,800 a month to $7,975. The full story of renovating and refinancing that Chattanooga duplex is in the BRRRR strategy guide.
I've also watched other investors do this dramatically, turning a single $300,000 condo into 14 units across three properties. The math compounds in your favor when you keep trading up and never stop to pay the tax.
How to decide what to sell
Not every property should be exchanged. I decide what to sell by looking at three things:
- Return on equity. A property sitting on a pile of trapped equity but producing mediocre cash flow is a candidate. Your equity could be working harder elsewhere.
- Time required. Problem properties that eat your attention are worth trading for newer, lower-maintenance ones.
- Criteria fit. Properties that no longer match your buy box.
This is why I review my portfolio's profit and loss statements every month. That habit tells me when to raise rents, when to refinance, and ultimately when to sell. My own strategy evolved over time, from "buy as many as I can and keep them forever" to actively trading up to replace my income faster. The underwriting that tells you whether the replacement is actually better is in how to underwrite a multifamily deal, and I run candidate replacements through DoorProfit to compare the numbers and the neighborhood before the 45-day clock ever starts.
The alternative when you don't want to sell
A 1031 has real downsides: you lose the original income stream, and that 45-day clock is brutal. Sometimes the better move is not to sell at all.
When I want to access a property's equity but keep the property, I use a line of credit against it instead. It taps the "stagnant equity" without a sale, which means no lost income and no taxable event, because borrowing isn't selling. The interest may even be deductible. I've used lines of credit this way to fund acquisitions and avoid expensive hard money, once saving nearly $900 a month in interest by replacing a 12% hard money loan. The tradeoff is that a line of credit is usually variable-rate debt, while a 1031 lets you fully redeploy into a bigger, better-cash-flowing asset. I break down the line-of-credit mechanics in how to finance a rental portfolio with other people's money.
So the real question isn't "1031 or not." It's whether you want to keep the property (borrow against it) or trade up out of it (exchange it).
The takeaway
A 1031 exchange is one of the most powerful tools the tax code gives real estate investors. It lets you sell an underperforming or maxed-out property and roll every dollar of gain, untaxed, into something that cash flows more and demands less of your time. Trade up enough times and you may never pay the capital gains tax at all.
The discipline is in the planning: line up your replacement before you sell, set up your intermediary early, respect the 45- and 180-day deadlines, and know going in how much (if any) boot you're willing to be taxed on. If you've got a property sitting on high equity and low returns, this is the conversation to have with your CPA this quarter. The hobby was never buying real estate. It's what you do with the real estate once you own it.
This article is educational and reflects my own experience. It is not tax or legal advice. 1031 exchanges are governed by strict IRS rules under IRC Section 1031 and mistakes can trigger the full tax bill, so always work with a qualified intermediary and your CPA before initiating one.
