It's an expensive time to buy a home in the U.S., with half of potential homebuyers saying they can't afford a down payment and closing costs on a new property.

But when it comes to affordability, or lack thereof, not all cities are created equal. In a recent study, Creditnews Research ranked the most populous U.S. cities by the percentage of neighborhoods financially within reach for the average married couple.

To create its ranking, Creditnews used median income for married households in order to determine the percentage of unaffordable neighborhoods. This figure was compared against the typical value of a home in each neighborhood, with areas deemed unaffordable if the monthly mortgage payment was higher than 25% of a couple's household income.

Of the 10 cities with the most unaffordable neighborhoods, four are in California. Two cities in the Golden State, Los Angeles and San Jose, were found to be 100% unaffordable for the average married couple household.

The city of angels, in fact, topped the ranking with the highest share of unaffordable neighborhoods in the U.S.

"L.A. has always been very expensive, but what we're seeing now is that average house prices and overall housing costs are far exceeding average income growth," Sam Bourgi, Senior Analyst at Creditnews Research, tells CNBC Make It.

He added that the pandemic "basically made a bad situation even worse in terms of affordability" for the capital of the entertainment industry.

"We're seeing a lot more residents of L.A. and the surrounding area spending much more of their income on housing every month," he added.

According to a 2022 U.S. Census Bureau report, the median household income in Los Angeles was $83,411. That's more than $150,000 less than the $237,281 household income needed to afford an average monthly mortgage of $5,932 in the California city, according to a 2023 Redfin report.

But it's not all bad news. The study found that cities in the Midwest, Rust Belt, and parts of the South still have plenty of affordability. Cleveland, Ohio, and Memphis, Tennessee, had 0% of unaffordable neighborhoods for the average married couple.

"There are affordable markets out there," Bourgi said. "You have to ask yourself if you're willing to move because they are going to be areas that people typically don't find as attractive."

These U.S. cities have the highest share of unaffordable neighborhoods

1. Los Angeles
2. St. Louis
3. Boston
4. San Jose
5. San Diego
6. San Francisco
7. New York City
8. Miami
9. Nashville
10. Richmond

St. Louis, Missouri ranked as the second most unaffordable housing market for the average married couple household, according to Creditnews Research.

The report found that 100% of the Mound City was unaffordable for the average family in 2024.

"What we're seeing is people holding on to their homes, making the supply of available homes very low, and that affects affordability," Bourgi says.

The average Saint Louis home value is $174,341, up 6.1% over the past year, according to Zillow.

St. Louis has a diverse economy and is home to seven Fortune 500 companies and over a dozen Fortune 1000 companies.

The Greater St. Louis area is also home to major research universities and offers residents family-friendly attractions like the Saint Louis Zoo and 1,300 acres of the picturesque Forest Park.

Boston, Massachusetts came in at no. 3 on the list with 100% of the city's neighborhoods out of reach for the average married couple.

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