The two-number housing calculator
What will this home really cost each month?
An ordinary mortgage calculator shows you the lender payment — principal, interest, taxes and insurance. That is the number used to approve you, not the number you live with. TrueCost shows that payment beside an estimated true monthly cost that also carries HOA dues, ongoing maintenance and mortgage insurance, so you can see the gap before you sign.
What the bank sees
Lenders qualify you on PITI: principal, interest, property taxes and homeowners insurance, plus mortgage insurance if you put down less than 20%. Guidance commonly cited by lenders keeps housing near 28% of gross monthly income and total debt near 36%.
What you pay
Your bank account also sees HOA dues, which are usually billed separately, and repairs and replacements. A widely used planning rule sets aside roughly 1% of the home's value per year for maintenance. Neither one appears in most quotes.
Why the gap matters
The difference between those two numbers is what surprises people after closing. Seeing it in advance lets you adjust the price, the down payment or the type of property while you still have a choice.
You
Used only for the affordability check. Nothing is sent anywhere.
Household total. If you are paid annually, divide by 12.
Car loans, student loans, minimum card payments, child support. Not utilities or groceries.
The house
Tax and insurance are editable planning examples. Replace them with property-specific figures whenever available.
ZIP and state are labels only; they do not fetch or change costs. Enter tax and insurance from the property record and an actual insurance quote whenever available.
$89,000 down · $356,000 borrowed
Annual percentage rate quoted by your lender.
State average. Your county assessor has the exact rate.
State average premium. Replace it with your quote when you have one.
Costs you can switch on or off
Cash needed at closing
Two costs
What the bank sees vs what you pay
The lender payment leaves out about $456 a month, or $5,470 a year.
Both figures are estimates, not a lender quote. A lender's number will differ once your exact tax bill, insurance premium, escrow schedule and loan terms are known.
Affordability check
Measured against the guidelines lenders commonly use.
Cash to close
What you need in the bank on closing day, plus a cushion for the months after.
| Down payment20% of price | $89,000 |
| Closing costs3% of price — lender fees, title, escrow, prepaids | $13,350 |
| Due at closing | $102,350 |
Closing costs vary widely by state, lender and loan type. Your Loan Estimate has the real figure.
Closing plus reserve
$112,163Includes a 3-month reserve of $9,813 at your estimated true monthly cost.
Detailed breakdown
Every line, monthly. Switched-off costs stay visible at zero so nothing is hidden.
| Line item | Per month |
|---|---|
| Lender payment | |
| Principal & interest | $2,339 |
| Property tax | $326 |
| Homeowners insurance | $150 |
| Mortgage insuranceNot required at 20% down | $0 |
| Lender payment | $2,815 |
| What the quote leaves out | |
| HOA or condo dues | $85 |
| Maintenance reserve | $371 |
| Estimated true monthly cost | $3,271 |
| Annual true cost | $39,250 |
| Left out of the lender quote each year | $5,470 |
| Total interest over the full termIf you keep the loan to term and never refinance | $485,921 |
Rent vs buy over 10 years
Cumulative housing cost if you buy now versus if you keep renting. Both paths include your money's opportunity cost.
The opportunity cost of not investing the down payment.
Appreciation, rent increases and investment returns are estimates. Small changes compound significantly over time. This chart is a planning guide, not a prediction.
Who this calculator is for
And when a different tool fits better.
This tool is built for someone who already has a specific home, or a realistic target price, and wants to see the lender's payment next to a fuller monthly number before signing anything. It works well for a first-time buyer comparing a Loan Estimate against their own budget, a buyer deciding whether a smaller down payment (and the PMI that comes with it) still fits, or an owner-to-be weighing HOA dues against a higher-maintenance older home with no HOA.
If you have not settled on a price yet, start with the Affordability calculator instead — it searches for a maximum price rather than pricing one home you already have in mind.
Common mistakes this tool is built to catch
- Comparing offers using only principal and interest, so a low-HOA home looks cheaper than a high-HOA home when the true monthly costs are close or reversed.
- Leaving PMI out of the comparison when a down payment is under 20%, which understates the real payment on the lower-down-payment offer.
- Treating the state default tax rate and insurance premium as the actual bill instead of replacing them with the county assessor's figure and a real insurance quote.
- Sizing the emergency reserve off the lender payment instead of the true monthly cost, which leaves it short exactly when maintenance or HOA increases hit.
- Assuming "front-end 28% / back-end 36%" is a rule you must meet rather than a common lender guideline that some loan programs and compensating factors can exceed.
Related guides and calculators
- Affordability calculator — find a maximum price instead of pricing one home.
- Cash to Close calculator — the same down payment and closing-cost assumptions, worked in more detail.
- Maintenance Reserve calculator — a more detailed reserve plan than the flat 1% default used here.
- How to read a Loan Estimate — compare this tool's numbers against the document your lender actually sends you.
- Buyer cost checklist — every cost to verify before and after this calculator.
Have a question?
Contact TrueCostHousing without opening an email application.
Methodology and disclaimer
Everything this tool assumes, written out.
Estimates only. Actual taxes, insurance, HOA fees, maintenance, rates, and lender requirements vary. Verify figures with your lender, county assessor, insurer, and HOA. This is an educational tool, not a loan offer, an appraisal, or financial advice.
How each number is calculated
- Principal & interest — standard amortization:
M = L · r(1+r)ⁿ / ((1+r)ⁿ − 1), where L is the loan amount, r is the annual rate ÷ 12, and n is the term in months. - Property tax — home price × tax rate ÷ 12. The rate is an effective annual rate, not a millage figure.
- Homeowners insurance — annual premium ÷ 12.
- Mortgage insurance — loan amount × PMI rate ÷ 12, applied only when the down payment is below 20%. It is included in the lender payment because lenders require it.
- HOA — the monthly amount you enter, added only when switched on.
- Maintenance — home price × the percentage you set ÷ 12, added only when switched on.
- Front-end share — lender payment ÷ gross monthly income. Commonly compared to 28%.
- Back-end share — (lender payment + other monthly debts) ÷ gross monthly income. Commonly compared to 36%.
- Real-life share — (true monthly cost + other monthly debts) ÷ gross monthly income. This is not an underwriting measure; it is a budgeting one.
- Cash to close — down payment + (home price × closing cost %) + the reserve months you choose, priced at the true monthly cost.
Where the state defaults come from, and their limits
The tool ships with one property tax rate and one insurance premium for each of the 50 states and Washington, DC — 51 entries in all. These are state-level averages compiled from published figures and are provided as a starting point only.
ZIP code is a label. Entering a ZIP does not look up county or ZIP-level tax data. Nothing is fetched. Rates within a single state vary substantially between counties and special districts, and insurance premiums vary by property, coverage and carrier. When you have a real figure from your county assessor or an insurance quote, type it in — the calculation uses whatever is in the field.
What this tool does not include
- Utilities, internet, trash, water and sewer.
- Special assessments, flood or earthquake policies, and umbrella coverage.
- Supplemental or reassessed taxes after a sale, and exemptions such as homestead caps.
- Escrow shortages, rate buydowns, points, seller credits, and lender-specific fees.
- Adjustable-rate loans. Every calculation assumes a fixed rate for the full term.
Your privacy
Every calculation happens in your browser. There is no account and no personal calculator input is sent as an Analytics event. Anonymous usage events may be collected to improve the site. Closing the tab clears your entries. If you use “Copy link”, your inputs are written into the link itself so the page can rebuild them — treat that link as private.