The 1% rule is the oldest screen in rental investing: a property should gross at least 1 percent of its purchase price in monthly rent. A $150,000 house should rent for $1,500. If it does not, skip it.
It is fast, it is memorable, and in 2026 it is wrong often enough that you should not make decisions with it alone. This post covers where the rule came from, exactly why it breaks at today's rates, where it still earns its keep, and the workflow that should replace it.
Where the rule came from
The 1% rule is folk wisdom from an era of very different math. When 30-year money cost 4 percent or less, a property clearing 1 percent rent-to-price almost always covered its mortgage, taxes, insurance, and reserves with room to spare. Investors needed a fast way to sort hundreds of listings, the ratio was computable from just two numbers on the listing itself, and the shortcut rarely lied. It spread because it worked.
The trouble with folk wisdom is that nobody sends a notice when the conditions that made it true expire. Rates roughly doubled, insurance repriced dramatically in large parts of the country, and property taxes marched upward. The rule's two inputs, rent and price, never heard the news.
What the rule actually measures
The 1% rule is shorthand for rent-to-price ratio, and rent-to-price is a proxy for cash flow. The proxy breaks because it ignores the three inputs that actually decide cash flow today:
- Interest rates. The same 1 percent property that cash flowed comfortably at a 4 percent mortgage can lose money at 7 percent. The rule has no rate input at all.
- Property taxes. Effective tax rates range from under 0.5 percent to over 2 percent of value per year depending on the state and county. On a $150,000 property, that swing alone is up to about $250 per month.
- Insurance. Premiums have climbed sharply in storm-exposed states. Two properties with identical rent-to-price ratios can sit hundreds of dollars apart in monthly cost.
The math of the break, in one table
Take a textbook 1 percent property: $150,000 purchase, $1,500 rent. Assume 25 percent down, ordinary reserves for vacancy and maintenance, management, and mid-range taxes and insurance. Roughly $780 of the rent goes to operating costs and reserves before the mortgage, leaving about $720 to cover debt service on the $112,500 loan. Now watch what the rate alone does:
| Mortgage rate | Monthly P&I | Approximate cash flow |
|---|---|---|
| 4.0% | about $537 | +$183 |
| 5.5% | about $639 | +$81 |
| 6.5% | about $711 | +$9 |
| 7.5% | about $787 | -$67 |
Same house, same tenant, same 1 percent ratio. At 4 percent it is a solid deal, at 6.5 percent it is a coin flip, and at 7.5 percent it quietly loses money. A screening rule that returns "buy" across that entire range is not screening.
Two properties can both pass the 1% rule and one will pay you every month while the other quietly loses money. The rule cannot tell them apart, because the things that separate them are not in the ratio.
Now add geography. Move that identical property from a 0.7 percent effective tax county to a 2.1 percent county and you subtract about $175 per month before anything else changes. Put it in a coastal wind zone and insurance can take another $100 over the national norm. The 1 percent ratio is silent on all of it.
Where the rule still helps
As a rejection filter, it remains genuinely useful. A property at 0.5 percent rent-to-price almost never cash flows at today's rates, no matter how friendly the taxes and insurance. If a listing is nowhere near 1 percent, you can usually skip the full underwrite and spend your ten minutes elsewhere. Rejecting fast is most of what screening is for.
The rule also still points you toward the right kind of market. Midwest and some Southern metros regularly produce listings at or above 1 percent, which is why cash-flow investors concentrate there. You can see how those markets look when every listing is fully underwritten on our live markets page, including Cleveland and Pittsburgh. The broader map, and the traits that make those metros work, are covered in Best Cash-Flow Markets for Rental Investors.
And in fairness to the old shortcut: within a single county, at a single point in time, comparing two similar properties, a higher ratio is still better than a lower one. The rule fails across markets and across time, not within a tight comparison.
Where it hides good deals
The rule cuts both ways. Because it ignores expenses, it also rejects deals it should not. Consider two properties:
| Property A | Property B | |
|---|---|---|
| Price | $150,000 | $150,000 |
| Rent | $1,650 (1.1%) | $1,350 (0.9%) |
| Effective tax rate | 2.2% | 0.6% |
| Monthly taxes | $275 | $75 |
| Insurance | $160 | $95 |
| HOA | $0 | $0 |
Property A passes the 1% rule with room to spare and hands $435 per month to the county and the insurer before reserves. Property B fails the screen but spends $170 on the same lines. Run both through the full math and B frequently comes out ahead. Investors who screen hard at exactly 1 percent throw B away without ever looking.
This matters most for duplexes and small multifamily, where two rents share one set of fixed costs and the expense side of the ledger behaves differently than the ratio suggests. We dig into that trade-off in Duplex vs. Single-Family.
A better five-second screen: derive your own ratio
If you like the speed of a ratio screen, you can keep it. Just derive the threshold from today's conditions instead of inheriting 2015's.
The logic: operating expenses and reserves typically consume 40 to 45 percent of gross rent on a well-underwritten cash-flow property (before the mortgage). Whatever remains must cover debt service with room to spare. So take a representative loan for your price point, compute its monthly payment at today's investor rate, divide by 0.55, and that is the gross rent the property needs. Divide that rent by the price and you have your personal minimum ratio for this rate environment.
Run the numbers and you will find the honest threshold today lands closer to 1.1 or 1.2 percent for a 25 percent down, fully reserved underwrite in a mid-tax state, and higher still in heavy-tax or heavy-insurance counties. That is the quiet reason so many listings that "pass the 1% rule" still fail a real underwrite: the rule's bar is simply below where the math now sits. When rates fall, re-derive and your bar drops with them, which is exactly when quick buyers pick up repriced deals ahead of the crowd.
Quick answers to the common variations
Is the rule based on gross or net rent? Gross. That is precisely its weakness: two properties with the same gross rent can have wildly different nets once taxes, insurance, and HOA fees land.
Does it include the down payment? No. The ratio knows nothing about your financing, your down payment, or your closing costs, which is why two investors can buy the same passing property and get completely different returns.
Should I use asking price or my offer price? Screen with asking, underwrite with your actual offer. A property that fails at asking can pass at your price, and that gap is where negotiation has real, computable value.
Does it work for short-term rentals? No. STR economics run on occupancy and nightly rates, with a completely different expense stack. The rule is a long-term-rental heuristic only.
What about the 2% rule?
You will still meet investors who insist on 2 percent. Those deals exist, but almost exclusively in the roughest pockets of the cheapest markets, where the ratio is compensation for tenant risk, capex risk, and neighborhoods most out-of-state buyers cannot manage remotely. A spectacular ratio is not a discount; it is a price. If a listing shows 2 percent, your next question should be why the market is paying you that much to own it.
What to use instead
Use the 1% rule for what it is: a five-second smell test. Then let the real numbers decide:
- Screen with rent-to-price to discard the obvious losers. Anything far below 1 percent in a cash-flow market is almost certainly dead at current rates.
- Underwrite the survivors fully: real rent (estimated properly, not inherited from the listing), the actual post-sale tax bill, a real insurance figure, vacancy and maintenance reserves, management, and today's actual investor mortgage rate. The complete checklist is in How to Analyze a Rental Property for Cash Flow.
- Rank by monthly cash flow, not by ratio. Ratios do not pay your bills; dollars do. Between two positive deals, the tiebreaker is cash-on-cash return, so a dollar of cash flow bought with less capital wins.
- Re-run the whole thing when rates move, because every deal's verdict is conditional on the cost of money. Your buy box is a function of the rate, whether you update it or not.
That workflow is exactly what PadSweep runs automatically on every for-sale listing in a market, every day: screen, underwrite with live rates and state-specific costs, reject everything that fails, and rank what survives by monthly cash flow. The 1% rule gets you to the right haystack. The full math finds the needles. If you want the whole sequence done for you, start a free trial.