Cap rate and cash-on-cash return get used interchangeably in listing descriptions and investor forums, and they should not be. They measure different things, they diverge the moment a mortgage enters the picture, and ranking deals by the wrong one will reorder your pipeline badly.
Two questions, two metrics
Cap rate asks: how good is the property, ignoring financing?
Cap rate = net operating income / purchase price
Net operating income (NOI) is rent minus operating expenses (taxes, insurance, vacancy, maintenance, management, HOA), before any mortgage payment. Cap rate is the property's unlevered yield: what the building earns as a business, independent of who buys it or how.
Cash-on-cash asks: how good is this deal for your money?
Cash-on-cash = annual cash flow after debt service / cash invested
Same property, but now your loan terms, your down payment, and your closing costs are in the equation. Full breakdown in Cash-on-Cash Return Explained.
The same property, two verdicts
Our worked-example duplex: $160,000 purchase, $1,106 monthly NOI.
| Metric | Value |
|---|---|
| NOI (annual) | $13,272 |
| Cap rate | about 8.3% |
| Cash flow after mortgage (annual) | $4,176 |
| Cash-on-cash (on $44,800 in) | about 9.3% |
Here CoC beats the cap rate, which means the financing is helping: the loan costs less than the property yields. That relationship is the whole game of leverage.
When your borrowing rate is below the cap rate, leverage amplifies your return. When your borrowing rate is above the cap rate, leverage amplifies your loss. That single comparison explains most of what changed for investors when rates rose.
At a 6.5 percent rate against an 8.3 percent cap, the spread works for you. Flip to a 5 percent cap rate market (typical of expensive coastal metros) with the same mortgage and the leverage runs backward: the more you borrow, the worse your CoC gets. This is why rates reshape your buy box and why cash-flow investors cluster in higher-cap markets.
When to use which
Use cap rate to:
- Compare properties on equal footing, since financing noise is stripped out.
- Compare a market's pricing over time or against other markets.
- Sanity-check a listing's pro forma (a claimed cap rate far above the market's norm usually means invented NOI).
Use cash-on-cash to:
- Decide where your actual down payment goes.
- Compare a rental against any other use of the same cash.
- Rank your deal pipeline, because dollars in your account, not unlevered yield, are what you can spend.
The honest hierarchy
For a leveraged buy-and-hold investor, the practical ranking is: monthly cash flow first, cash-on-cash second, cap rate as the diagnostic. Cash flow is survival (a negative number ends the discussion), CoC is efficiency, and cap rate explains why the first two look the way they do.
That is precisely the ordering PadSweep uses when it ranks a market's listings: deals are sorted by monthly cash flow with CoC as the tiebreaker, and every metric is computed from the same full underwrite (real taxes and insurance by state, reserves, and live mortgage rates). You can browse ranked deals by market or run your own search with a free trial.