What 28 Percent Doesn't Cover: The Real Cost of a 2026 Mortgage

As of August 27, 2026, Freddie Mac's Primary Mortgage Market Survey put the average 30-year fixed rate at 6.66 percent, essentially flat with the 6.65 percent recorded the week before and only a tenth of a point above the 6.56 percent recorded a year earlier. Meanwhile the median price of an existing home sold in July 2026 reached $434,100, up 2.0 percent from $425,700 a year earlier, according to the National Association of Realtors. The Federal Housing Finance Agency's house price index tells a similar story at the national level: prices rose 2.1 percent between the second quarter of 2025 and the second quarter of 2026, and 0.3 percent from the first quarter of 2026 to the second, extending a run of positive annual appreciation that has held every quarter since 2012. Against that backdrop, most buyers still reach for the same shorthand their parents used: spend no more than 28 percent of gross income on housing. That rule was built for a mortgage payment. It was never built for a mortgage payment plus private mortgage insurance plus a homeowners association fee plus a homeowners insurance bill that, in a growing number of states, has stopped behaving like a rounding error.

Run the math on that July median price at the current rate. A buyer putting 20 percent down finances $347,280 and, at 6.66 percent over 30 years, owes roughly $2,232 a month in principal and interest alone. Put down 10 percent instead and the loan grows to $390,690, pushing principal and interest to about $2,511. Now compare that to the income side of the equation. The Census Bureau's most recent household income data — for calendar year 2024, the latest available, since the 2025 figure is not due until September 2026 — put median household income at $83,730, a figure the Bureau describes as not statistically different from the $82,690 recorded in 2023. Twenty-eight percent of that income comes to $1,954 a month. Principal and interest on the median-priced home, financed with a full 20 percent down and nothing else added, already exceeds the entire monthly housing allowance the 28 percent rule grants a median-income household — before property taxes, before insurance, before a single line item this piece is about to add.

For the large share of buyers who cannot put 20 percent down, private mortgage insurance is not optional. Lenders require it on a conventional loan whenever the down payment falls below 20 percent, and the same threshold usually applies on a refinance if the borrower's equity has fallen below 20 percent, according to the Consumer Financial Protection Bureau. It does not last the life of the loan. Under the Homeowners Protection Act, PMI must terminate automatically once the loan balance is scheduled to reach 78 percent of the property's original value, provided the borrower is current on payments, and a borrower can request cancellation earlier, once equity reaches 20 percent, or 80 percent loan-to-value. That makes PMI a real but time-limited cost: a 20-percent-down buyer skips it entirely, while a 5-or-10-percent-down buyer carries it for years on top of the higher principal-and-interest payment that comes with financing a larger share of the purchase.

Homeowners association and condo fees sit entirely outside the mortgage and are just as easy to underweight. The Census Bureau's 2024 American Community Survey put the national median HOA or condo fee at $135 a month, with mortgaged households paying a median of $120 and paid-off households paying $184 — and it is not a fringe cost, since 21.6 million of the nation's 86.6 million owner households were paying one. A buyer who budgets only for principal, interest, taxes and insurance and then discovers a monthly HOA fee attached to the specific property they want has effectively been underwriting the wrong number for months.

The least predictable line item, and the one the 28 percent rule was never built to anticipate, is homeowners insurance in a climate-exposed market — and it is moving in opposite directions depending on where a buyer is looking. In Florida, regulators are reporting relief after years of crisis: Citizens Property Insurance is cutting rates by a statewide average of 8.7 percent for more than 330,000 policyholders across all 67 counties, with reductions reaching 14.1 percent in Broward County and 14.0 percent in Miami-Dade County, and the Florida Office of Insurance Regulation reports rates have fallen in 51 counties so far in 2026, a stretch in which 44 carriers have filed for rate decreases and another 48 have filed for flat renewals since 2024. California is moving the other way. The state's Department of Insurance approved a 29.1 percent average rate increase for the FAIR Plan, effective October 15, 2026, affecting roughly 675,000 to 700,000 policyholders — driven by a FAIR Plan exposure base that grew to $768 billion by June 2026, an 11 percent jump in nine months, against a cash cushion of only $200 million to $400 million; policyholders in the highest wildfire-risk areas could see premiums double. Two regulated markets, same country, same year, opposite trajectories. A homeowners insurance line item cannot be estimated from a national average. It has to be underwritten property by property.

Stack those pieces against the median-priced, rate-and-income picture above and the honest answer is unflattering: the 28 percent rule of thumb understates the true cost of carrying a median-priced home in 2026, not by a rounding error but by a margin large enough to change whether a household actually qualifies. A household earning the national median income cannot cover principal and interest on the median-priced home within a 28 percent budget even with a full 20 percent down, and every dollar of PMI, HOA fee or elevated insurance premium on top of that only widens the gap. The industry's own broader affordability gauge, the National Association of Realtors' Housing Affordability Index, registered 103.3 in July, up from 98.3 a year earlier — nominally on the affordable side of the line — but that index measures a national median family against a national median home price and mortgage payment. It does not know whether the specific property carries an HOA fee, whether the buyer needs PMI, or whether the specific address sits in a Florida county getting rate relief or a California wildfire zone getting a 29 percent increase. Two households can look identical on paper, same income, same qualifying ratio, and still carry meaningfully different true monthly costs once the property-specific line items are added in.

What this means in practice: before treating any percentage-of-income rule as an affordability ceiling, a buyer needs the property-specific numbers, not the national averages — the actual PMI quote at the actual down payment, the actual HOA disclosure, and an actual insurance quote for that address, not a statewide or national figure, because the same year is producing double-digit rate cuts in parts of Florida and a 29 percent hike in California's highest-risk FAIR Plan pool. A buyer working within the 2026 conforming loan limit of $832,750 has plenty of room on the financing side at the median home price; for most households the binding constraint is monthly cash flow once PMI, HOA fees and insurance are added to principal and interest, not loan eligibility. That distinction holds at every scale this platform serves — a portfolio underwriting single-family rentals or a family office evaluating a coastal second home needs the same per-property insurance and carrying-cost discipline as a first-time buyer, just applied across more doors. Treat the 28 percent rule as a conversation starter, not a number to build an offer around.