The mortgage lock-in effect gets talked about mostly as an inventory problem. Sellers won’t list because giving up a 3% rate for a 7% rate costs them $800 or $1,000 a month. True enough. But there’s a side story that doesn’t get nearly as much attention: a growing number of homeowners who genuinely need to move — job change, new baby, divorce, upsizing — but can’t stomach selling. So they rent the place out instead. They become landlords by default. Not by plan, not by strategy, just by circumstance.

Call them accidental landlords. They’re everywhere right now, and in a market like Metro Phoenix, they’re reshaping the rental landscape in ways that are easy to miss.

How the Lock-In Effect Creates Reluctant Investors

Here’s the math that’s trapping people. A homeowner who bought in Gilbert or Chandler in 2020 or 2021 locked in a 30-year fixed rate somewhere between 2.75% and 3.25%. Their monthly principal and interest on a $380,000 home sits around $1,580. That same home is worth roughly $460,000–$480,000 today. If they sell and buy something comparable — or even slightly larger — they’re financing at current rates hovering near 6.6% to 7%. Their new payment jumps to $2,800 or more. That’s not a small difference. For a household making $110,000 a year, that’s the difference between manageable and genuinely painful.

So what happens when life forces a move anyway? A lot of them keep the house.

The math on renting it out often works. That same Gilbert home rents for $2,100–$2,400 per month in today’s market. The owner’s PITI (principal, interest, taxes, insurance) might be $1,900–$2,050. That’s thin — sometimes negative once you factor in a property manager at 8–10% of gross rent — but it preserves the asset. It keeps the low-rate mortgage alive. And psychologically, it feels better than “giving up” the rate.

Arizona Is Ground Zero for This Trend

Phoenix and its suburbs saw some of the fastest price appreciation in the country between 2020 and 2022. That means more homeowners here are sitting on both significant equity and unusually low rates — a combination that makes the lock-in calculus especially sharp.

As of recent market data, roughly 60% of outstanding Arizona mortgages carry rates below 4%. Nationally, the figure is around 57%. The spread isn’t huge, but Phoenix buyers skewed heavily toward purchases in the 2020–2022 window, so the concentration of sub-4% paper here is real.

The result: the Phoenix housing market has been stuck in a stalemate for months, with sellers reluctant to list and buyers frustrated by thin inventory. The accidental landlord phenomenon is one of the quieter drivers of that gridlock. Instead of listings hitting Zillow, homes are quietly absorbed into the rental pool.

What Accidental Landlords Are Actually Getting Into

Most people who stumble into landlord status underestimate what’s involved. A few things they typically don’t anticipate:

  1. Tenant screening costs time and judgment. A bad tenant in Tempe or Peoria can cost you $8,000–$15,000 in unpaid rent, legal fees, and repairs. Most first-time landlords don’t have an eviction attorney on speed dial.
  2. Arizona landlord-tenant law has specific timelines. Written move-in checklists, security deposit return within 14 business days, notice requirements for entry — small violations can become liability.
  3. Capital reserves matter. A $6,000 HVAC replacement in August (and in Phoenix, HVAC failure in August is a real emergency) wipes out months of cash flow.
  4. Property management fees compress margins. On a $2,200/month rental, an 8% management fee is $176/month. Add maintenance, vacancy, and insurance, and “positive cash flow” can turn negative fast.
  5. Rental income is taxable. Unlike a primary residence, there’s no capital gains exclusion for rental property if they sell more than three years after moving out. Tax planning matters from day one.

That last point trips people up more than any other. They convert their home to a rental, assume they can sell later and pocket the gain tax-free — and then learn the rules changed the moment they stopped living there.

What This Means for Buyers and Renters

For renters, the accidental landlord wave has added single-family homes to a rental market that used to be dominated by apartment complexes and institutional build-to-rent operators. Projects like Avilla Foothills in Surprise represent purpose-built rental inventory. Accidental landlord stock is different — it’s scattered, inconsistently managed, and priced based on what the owner needs rather than what the market will bear. Sometimes that means a deal. Sometimes it means an amateur landlord who doesn’t respond to maintenance calls.

For buyers, this inventory is essentially invisible until it isn’t. When rates eventually drop enough to break the lock-in math — most analysts peg that threshold at somewhere around 5.5% on 30-year fixed — a wave of these homes could hit the resale market simultaneously. It won’t happen overnight, but the inventory is sitting there, waiting.

For investors watching the Phoenix single-family rental market, the accidental landlord cohort is also a competitor. They’re often willing to accept below-market yields because their carrying costs are so low. On a 3% mortgage, they can undercut a newer investor financing at 7% and still break even.

What You Should Do If You’re In This Position

If you’re staring down a move and wondering whether to sell or rent your current home, here’s how to think through it clearly:

The affordability math across the Phoenix market has improved slightly from its 2023 peak, but carrying two properties — your old one as a rental and a new purchase — is still a significant financial stretch for most households. The lock-in effect created this situation. Recognizing it clearly, rather than sleepwalking into accidental landlordism, is the first step toward making the right call for your specific circumstances.

Wherever you land — sell, rent, or stay put — make the decision with clear numbers in front of you. That’s what separates a strategy from a trap.