The median home price in Suffolk County rose to a record high in May, while the pace of appreciation for single-family houses in Nassau County slowed last month.

In Suffolk County, the median price of a single-family home increased 6.2% to an all-time high of $690,000 in May compared with the same figure a year earlier, according to new data released Monday by OneKey MLS.

In Nassau, the median rose 2.5% from the previous year to $810,000. That is below the all-time high of $835,000 recorded in August. Last year at this time, the median price increased 13% compared with the same figure a year earlier.

Even as home prices in Suffolk hit a record high, they are rising at a slower pace than last year — welcome news for buyers after several years of rapid increases. But agents said sellers continue to hold power in the market because of a lack of homes for sale.

"The increases seem to be falling a little bit, but [prices] are still increasing," said Richard Haggerty, CEO of OneKey MLS. "That shows you buyer demand is still strong. It does have to reach the peak at some point."

There were 5,072 houses for sale on Long Island at the end of May, according to OneKey, which was down 5% compared with the previous year. There are still fewer than half as many listings as there were in May 2019 before the pandemic.

Haggerty said he was disappointed that there wasn’t a larger wave of new listings during the typically busy spring season. The lack of options has deterred homeowners from upgrading or downsizing to a new home, he said.

"This is our new normal for now, and I think sellers are going to continue to play a waiting game," Haggerty said. "I see the price acceleration continuing to slow, but I don’t see any steep reduction in the median sale price in the future."

Fewer listings have led to a smaller number of transactions. There were 1,400 closings in Nassau and Suffolk combined in May, or 9.6% fewer than at the same time a year ago.

The easing of the market has been more noticeable among higher-priced homes, said Bryan Karp, an associate broker at Coldwell Banker American Homes in Smithtown.

Listings priced below $800,000 still often attract significant interest from buyers, who often must compromise certain items on their wish list, such as a pool or a detached garage, he said.

"If you’re in that sweet spot, it’s still almost impossible to get a house," Karp said of buyers searching between $500,000 to $800,000. "We don’t have the amount of buyers we had during COVID, but it’s the same feeding frenzy in the first-time homebuyer price point."

Making matters worse for buyers, mortgage rates have not fallen below 6% since September 2022, which has made it more expensive to finance a mortgage than it had been a few years ago.

The average rate for a 30-year fixed mortgage was 6.84% for the week ending Thursday, according to Freddie Mac. The average has not fallen below 6.6% in any week this year.

Sellers with lower mortgage rates continue to stay put unless a major life event forces their hand, said Jonathan Chandler, an agent at Compass in Rockville Centre. That means buyers have little leverage to negotiate the terms of a deal, he said.

"It’s still a seller’s market right now," said Chandler, who represents buyers and sellers in Nassau, Suffolk and Queens counties. "It’s not at a point where buyers are able to negotiate a slew of different terms in their favor."

Long Island has stood out among U.S. real estate markets, which have started to more significantly favor buyers, according to a recent report from real estate brokerage Redfin. That report found Long Island was the second-strongest seller’s market, behind only Newark, among the 50 largest U.S. metro areas tracked by the brokerage.

Buyers had the most leverage in Florida markets, including Miami, West Palm Beach and Fort Lauderdale as well as Austin, Texas, and Phoenix, Arizona, according to Redfin.

Those markets have as many or more homes available now than were available before the pandemic and benefit from higher levels of new construction than occurs on Long Island, said Chen Zhao, head of economics research at Redfin. 

"Nassau and Suffolk are still far below where we were pre-pandemic" in terms of inventory, she said. "Nationally, we’re almost back to where we were pre-pandemic. That’s what’s really the difference and why Long Island is one of the stronger markets right now."