The short version: lenders do not qualify you on the sticker price, they qualify you on the monthly payment. At the 6.71% model rate (Freddie Mac average, week of September 3, 2026) the payment on $100,000 is $944 with the smallest FHA down payment, and the income that supports it lands between $26,348 and $36,547 depending on how much other debt you carry. Every table below is that one calculation, re-run at each rate and in each place.
What a $100,000 house costs each month
The payment has four parts: principal and interest ($634 at 6.71% with 3.5% down), FHA mortgage insurance ($45), and property tax plus home insurance ($265, the median of the 80 metros in the Foothold dataset). Taxes are the part that moves most from place to place, and the table after this one shows how far.
| Mortgage rate | 3.5% down (FHA) | 20% down (conventional) |
|---|---|---|
| 5% | $837 | $694 |
| 5.5% | $867 | $719 |
| 6% | $899 | $745 |
| 6.5% | $930 | $771 |
| 6.71% (model rate) | $944 | $782 |
| 7% | $963 | $797 |
| 7.5% | $996 | $824 |
The income you need for a $100,000 house at each rate
Two guidelines, not one: FHA’s front-end ratio says the housing payment should stay under 31% of gross income. Its back-end ratio says all debt together should stay under 43%. A buyer with no car loan, no student loan and no card balance can qualify near the 43% line; a buyer carrying $500 a month of other payments is pushed back toward the 31% figure. Real approvals land between the two.
| Mortgage rate | Payment (3.5% down) | Income at 31% (front-end) | Income at 43% (back-end, no other debt) |
|---|---|---|---|
| 5% | $837 | $32,399 | $23,357 |
| 5.5% | $867 | $33,576 | $24,206 |
| 6% | $899 | $34,783 | $25,076 |
| 6.5% | $930 | $36,019 | $25,967 |
| 6.71% (model rate) | $944 | $36,547 | $26,348 |
| 7% | $963 | $37,282 | $26,878 |
| 7.5% | $996 | $38,571 | $27,807 |
From the other direction: what house a $40,000 salary buys runs the same numbers starting from the paycheck instead of the price.
How local taxes and insurance change the payment on $100,000
The same $100,000 house carries a $842 payment in Washington, DC and $1,281 in Jacksonville, FL, a gap of $439 a month, most of it home insurance. That gap is worth $16,989 of qualifying income on the front-end guideline, which is why a price that is out of reach in one metro is comfortable in another on the same salary.
| Metro | Effective tax rate | Tax + insurance a month | Payment on $100,000 | Income at 31% |
|---|---|---|---|---|
| Washington, DC | 0.78% | $163 | $842 | $32,604 |
| Salt Lake City, UT | 0.54% | $168 | $848 | $32,812 |
| Las Vegas, NV | 0.79% | $170 | $850 | $32,893 |
| Jacksonville, FL | 1.24% | $602 | $1,281 | $49,593 |
| Tampa, FL | 1.24% | $602 | $1,281 | $49,593 |
| Orlando, FL | 1.17% | $596 | $1,275 | $49,367 |
Where $100,000 buys a duplex instead
The part most buyers miss: on a two-to-four-unit home the lender counts 75% of the other unit’s rent as your income. At $100,000 no metro in the 83-metro dataset has a duplex entry price under that budget, so the shortcut starts higher up the price ladder. The Foothold Index lists every metro’s entry price.
The down payment on a $100,000 house
Where these numbers come from
- Mortgage rate: 30-year fixed, Freddie Mac Primary Mortgage Market Survey, week of September 3, 2026: 6.71% is the model rate used throughout; the tables re-run the same payment at each rate.
- Loan terms and mortgage insurance: FHA 3.5% minimum down payment, 1.75% upfront and 0.55% annual mortgage insurance premium, HUD Handbook 4000.1. Qualifying ratios: FHA 31% front-end and 43% back-end, same handbook. Rental income credited at 75%, the lender convention for two-to-four-unit homes.
- Property taxes: county effective rates for 80 metros. Insurance: state average premiums scaled to price. The national row is the median of those metros, not a US average.
- FHA loan limits: HUD CHUMS CY2026 forward limits by county, one-unit and two-unit columns.
- Duplex entry prices and rents: the Foothold dataset, active two-to-four-unit listings screened Jun-Aug 2026; the one-bedroom rent is the average of Zumper and Apartment List metro asking rents (May to July 2026), which the model scales per ZIP by HUD FY2026 Small Area Fair Market Rents.
- Area median income and the 80% limit: HUD FY2026 Income Limits (Section 8), huduser.gov.
- All of it, as one file: the open data page (CC BY 4.0).
Figures are estimates for comparison, not a loan quote. Your lender prices your rate, your county sets your tax bill, and your credit file sets your ratios. Verify before you offer.
Questions people ask about a $100,000 house
Can I afford a $100,000 house on $30,000 a year?
A $100,000 house costs about $944 a month with 3.5% down at 6.71%, which is 38% of a $30,000 salary. That sits between FHA’s 31% and 43% guidelines, so it works with little or no other monthly debt. At $20,000 the payment is 57% of income, over the 43% line. A bigger down payment, a lower rate or a duplex with a rent-paying unit each pull the ratio down.
What is the monthly payment on a $100,000 house?
The monthly payment on a $100,000 house is about $944 with 3.5% down and $782 with 20% down at 6.71%, including property tax and insurance at the median of the metros in the dataset. Principal and interest is the largest piece; FHA mortgage insurance and the local tax rate make up most of the rest.
How much do I need to put down on a $100,000 house?
The minimum down payment on a $100,000 house is $3,500 with an FHA loan (3.5%), plus closing costs of roughly 2% to 3% of the price. Conventional loans start at 3% to 5% down for first-time buyers, and 20% down ($20,000) removes mortgage insurance entirely.
Does buying a duplex change the income needed for $100,000?
Buying a duplex changes the income needed because the lender credits 75% of the second unit’s rent, which lowers the payment you have to qualify for. At $100,000 no metro in the dataset has a duplex entry price under budget, so that credit starts at higher price points.
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