Why Turning A Primary Residence Into A Rental Is A Bad Idea

If you’re thinking about or already have turned a primary residence into a rental, you might want to rethink that. Even if your property is allegedly in a “high appreciation” market, it still may not make financial sense to hold on to it. To understand why, it all comes down to a numbers game, especially taxes. In this post, I will share why I decided to sell my very 1st primary residence instead of turning it into a rental, how I determined that was the best financial decision, and the numbers to back up my decision.

Is it even legal to turn a primary home into a rental?

Before I dive into my home sale and all the numbers behind it, I first want to call out the legality behind turning a primary residence into a rental. If you purchased the home entirely with cash, then you have no loan. That means you can pretty much do what you want with the home (unless renting it out is forbidden by your HOA).

However, most people purchase a home with a loan. When you do that, the terms of your loan specifically state the intended use of the home. So if you tell the lender it’s going to be your primary residence (owner occupied), you can’t use the home as a rental immediately after purchasing it. If you do, that’s bank fraud and can result in jail time!

In most cases, people do live in it for a while and then consider turning it into a rental after several years. Is it legal to do this at that point? Well, the answer is that it depends. I strongly recommend you contact your lender to find out. You don’t want to wind up in a situation that’s potentially fraudulent.

To play it safe, I think turning a primary home into a rental can be done by simply refinancing your home and replacing your owner-occupied mortgage with an investment property mortgage. That way, the terms of your loan legally allow you to rent out the home.

Do the numbers even make sense?

Back in 2012, I purchased my 1st home for $390,000. In 2015, I sold my home for $650,000. 

Five years after that sale, the home was worth about $800,000, meaning had I kept the home, it would’ve appreciated an additional $150K. Additionally, if I turned it into a rental, how much rental income would I have brought in over those 5 years? The answer comes out to roughly $6,000 per year plus principal pay down of my mortgage, totaling about $50K of additional cash to me (forget about taxes for simplicity’s sake). 

The question I have to ask myself is, “Have I made more money from the proceeds of my home sale over those 5 years, or would I have made more money by renting it out?” First, let’s talk about the sale of my home. Because I lived in my home for at least 2 years between 2012 and 2015, selling my home qualified for the home sale tax exclusion rule?Home Sale Tax ExclusionA tax break allowing you to pocket up to $250,000 in capital gains ($500,000 for married couples) tax-free when selling your primary residence, as long as you lived in it for at least 2 of the past 5 years.. The rule states that if you live in a home for 2 of the past 5 years, you do not have to pay capital gains taxes on the first $250,000 in profit ($500K if you’re married and you both own the home jointly!). So my $650K home sale, minus 6% in sales commissions, came out to $611,000. Subtracting my purchase price of $390K, my profit was $221,000. Therefore, using the home sale tax exclusion rule, I paid $0 in taxes and pocketed the entire profit!

Alright, so I had $221,000 in cash, plus about $100K in equity I had in the house. Therefore, I had $321K of cash to invest elsewhere. Investing that $321K into the S&P 500 in 2015 turned into $675K within 5 years (a $354K profit), and over $1.1 million by 2026!

On the other hand, had I kept the home during the same 5-year timespan, I would’ve forfeited the 2-out-of-5-year residency test once rented for more than 3 years. Even if we generously applied the $250K home sale tax exclusion rule on an $800K home sale, my profit would’ve been $362K, leaving $112K taxed at 20% long-term capital gains?Long-Term Capital GainsProfits earned from selling assets you owned for longer than one year, which are taxed at preferential rates (0%, 15%, or 20%) rather than standard paycheck income tax rates. ($339,600 net proceeds). In reality, waiting 5 full years after moving out disqualifies the entire $362K gain from Section 121, triggering over $72,000 in federal and state capital gains and depreciation recapture taxes!

Here’s a summary of what all those numbers look like:

The "3% Mortgage Lock-In" Trap: Return on Equity (ROE) vs. Cash Flow

Today, the #1 reason homeowners hesitate to sell their former primary residence is a sub-3.5% mortgage rate locked in during 2020 or 2021. On paper, collecting $3,500 per month in rent against a $2,400 monthly mortgage payment looks like $1,100 per month in effortless passive income. However, evaluating an accidental rental by gross mortgage spread ignores Return on Equity (ROE).

Suppose your home is worth $850,000 with a $350,000 mortgage balance at 3.0%. After subtracting 6% in selling costs ($51,000), you have $449,000 in net unlockable equity sitting inside the property. Once you deduct realistic landlord operating expenses (8% property management, 5% vacancy, 8% maintenance and CapEx reserves for roof/HVAC, plus higher DP-3 landlord insurance), that $1,100 monthly spread shrinks to roughly $450 per month ($5,400 per year) in true net cash flow.

Dividing $5,400 in annual net cash flow by $449,000 of trapped equity yields a paltry 1.2% cash Return on Equity. Even a risk-free U.S. Treasury Bill ladder or a diversified stock index portfolio earns 3x to 7x more on that exact same $449,000 without midnight plumbing emergencies or tenant turnover.

The IRS Section 121 Tax Cliff & 25% Depreciation Recapture

Converting a highly appreciated primary residence into a rental starts an irreversible IRS tax countdown:

• The 3-Year Section 121 Deadline: Under IRS Section 121, you must have owned and lived in the property as your primary residence for at least 24 months out of the 60 months (5 years) leading up to the closing date of the sale. Once you move out and rent the house for 3 years and 1 day, you fail the 2-out-of-5-year test and lose up to $250,000 (single) or $500,000 (married filing jointly?Married Filing Jointly (MFJ)A federal tax filing status for married couples that doubles standard deduction thresholds and income tax bracket widths compared to single filers.) in tax-free capital gains exclusion. For a high-income couple in a combined 23.8% federal (20% LTCG + 3.8% NIIT) plus 9% state tax bracket, missing that deadline on a $500,000 gain triggers an immediate $164,000 tax bill.
• Mandatory 25% Depreciation Recapture (Section 1250): Even if you sell before the 3-year deadline expires, the IRS requires you to recapture all "allowed or allowable" residential depreciation taken during the rental period at up to a 25% federal tax rate. Section 121 never shields rental depreciation recapture.
• Cost Basis?Cost BasisThe original money you paid for an investment plus reinvested dividends. When you sell, you are only taxed on your actual investment profits above this number, never on your original cash. Step-Down Rule: If your home's market value ever drops below your original purchase basis at the time of conversion, the IRS forces you to use the lower fair market value as your starting basis for depreciation and loss calculations.

When Converting a Primary Home to a Rental Actually Makes Sense

While turning a high-equity primary residence into a rental is usually a mathematical trap, there are three narrow scenarios where holding the property works:

1. Minimal Unrealized Capital Gains: You bought the home recently, have very little appreciation at risk of losing the Section 121 exclusion, and the rent covers PITI plus a 15% maintenance and vacancy reserve.
2. Strict 30-Month Exit Plan: You rent the home for 18 to 24 months to test a new city or job, then list and close on the sale well before Month 36 so you capture 100% of the Section 121 exclusion (minus minor depreciation recapture).
3. Permanent 1031 Exchange?1031 ExchangeA real estate rule that lets you sell an investment property and roll the full sale proceeds into a new property while postponing all capital gains and depreciation recapture taxes. & Step-Up in Basis?Stepped-Up BasisA tax benefit where the cost basis of inherited assets (like real estate or stocks) resets to fair market value on the day the owner passes away, wiping out all capital gains taxes earned during their lifetime. Estate Strategy: You intend to hold the property or swap it via IRS Section 1031 like-kind exchanges for the rest of your life so your heirs eventually receive a stepped-up cost basis under Section 1014, eliminating both capital gains and depreciation recapture at death.

So instead of blindly assuming that turning a primary residence into a rental is always the right financial decision, I strongly urge you to run the numbers, factor in the home sale tax exclusion rule, and consider the full opportunity cost?Opportunity CostThe potential return or benefit you give up by choosing one financial option over another, like the future compound investment returns lost when spending money today. before deciding! I will admit that if your home has a reasonable profit margin as a rental, it’s probably not a bad choice, but is it the best? Well, that’s highly dependent on your unique property and how the numbers play out!

Before holding onto residential real estate, evaluate alternative wealth-building vehicles. Review our analysis of why stock market investing builds enduring wealth, compare primary residence vs. stock market returns, or test your numbers with our free Real Estate Evaluation Tool.