How Much Rent Can You Afford? The 30% Rule and the Salary Math

Take your gross annual salary, multiply it by 0.30, then divide by 12, and the number you get is your monthly rent ceiling under the 30% rule, so a $60,000 salary would be $1,500 a month while a $100,000 salary lands at $2,500. The rule has survived decades of financial advice mostly because you can run it in your head, and because at 30% there's still room in a budget for groceries, gas, insurance, and everything else that isn't rent.

Two things complicate it though.

What 30% of your salary actually buys

Here's a table, with gross salary next to the rent it supports at 30%.

At $40,000 you've got $1,000 a month to work with, and $100,000 gets you to $2,500, which opens up most of the country. The jump from $75,000 to $100,000 adds $625 of monthly headroom as the rule moves in a straight line: every extra $1,000 of annual pay lifts the ceiling by exactly $25 a month, or $300 across a year. A $5,000 raise buys $125 a month of rent.

The gross income catch nobody prices in

The 30% rule measures gross income, which is your pay before taxes and payroll deductions come out, but rent gets paid out of take-home money, and those two numbers sit a long way apart. A worker earning $75,000 gross might see closer to $57,000 after federal tax, state tax, social security, and payroll deductions, so there's an $18,000 annual difference the rule doesn't account for anywhere.

The rule calls $1,875 affordable, and when you measure that same $1,875 against $57,000 in real take-home pay, it's closer to 39% of the money that lands in the account.

So treat every figure in the table as a ceiling and aim under it, either by running the rule against take-home pay so it protects your budget the way it was designed to, or by holding your rent a few hundred dollars below the gross-income number. Our affordability calculator will pressure-test a salary against a specific market.

Where the $1,951 median rent sets the bar

The US national median rent is about $1,951 a month, and the median US wage sits well below the salary that rent implies, so a renter earning near the middle is already past the guideline in a large share of markets. Run the rule backward and you can see why, because a $1,951 rent takes roughly $78,000 in gross salary, or $6,500 a month before taxes.

Why a six-figure salary still falls short in pricey cities

At the top of the price map the rule stops describing anything you can reach. A typical rent in San Francisco runs about $4,253 a month, which is $51,036 a year in rent alone, and holding that to 30% of gross takes roughly $170,000 in salary.

Keep in mind that $4,253 is the ordinary going rate across the city, so a $125,000 salary affords $3,125 by the table and falls more than $1,100 short, while a $150,000 earner clears $3,750 and still sits roughly $500 under the local median.

In the priciest metros the rule is telling you something true about a market where the math doesn't work on a normal salary, so renters there blow past 30%, split the rent with someone, or leave town. Cheaper cities run the other direction, since a $60,000 salary clears $1,500 there and that covers a comfortable one-bedroom.

How to use the rule without getting burned

Treat 30% of gross as a line you don't cross, then aim below it and price the specific unit against your take-home pay, because that's the money you'll actually be handing over. If a market's typical rent needs an income you don't earn, believe the number and adjust where you're looking.

Before you tour anything, run your own ceiling: salary times 0.30, divided by 12, then take about 10% off for the tax gap. On $75,000 that's $1,688 a month.

Rents cited here come from RentDataNow, anchored to the Zillow Observed Rent Index (ZORI).