The state’s housing market started 2018 like it was still 2017 — with higher prices and fewer homes for sale.

For the second consecutive month, the number of single-family homes for sale in Massachusetts fell below 10,000 in January. It marked a record low for the month, which typically is a slow time in the real estate business.

Single-family home sales in January were slightly down — 1.2 percent — compared with the same period last year, while the median price jumped 4 percent to $369,000, according to the Massachusetts Association of Realtors.

For condominiums, the median price increased more than 6 percent to $355,000 for the month of January, while sales fell by about 7 percent.

The Warren Group, which tracks a larger pool of real estate transactions in Massachusetts, said single-family home sales in January dipped less than 1 percent from the prior year. It also reported a 2 percent median price increase, to $350,000, which the Boston-based company said set a record for the month.

“Although single-family home sales declined ever so slightly, the increased median home price is a good indicator that 2018 could be another record-setting year,’’ Warren Group chief executive Tim Warren said.

January’s $345,000 median price for condos was also the highest the Warren Group has recorded. Meanwhile, condo sales fell 1.6 percent, year-over-year.

A lack of inventory continues to be the dominant theme of the housing market in Massachusetts. The number of single-family homes for sale in January decreased by 32 percent over the same time last year, while the number of condos up for sale dropped by 7 percent, according to the realtors association.

“It is challenging to start out the new year with such a deficit of housing inventory,’’ said Rita Coffey, who is president of the association and general manager of Century 21 Tullish & Clancy in Weymouth.

On average, single-family homes spent nine fewer days on the market in January, compared with the same time last year. Condos were on the market 10 fewer days.

Coffey said the crunch can only be eased by building more new homes. “Unfortunately,’’ she said, “Massachusetts residents selling their homes will not be enough to recover.’’

-1.2%

Drop in single-family home sales in Massachusetts in January compared with the same period last year.

4%

Increase in the median price, to $369,000, in the same period.

Katheleen Conti can be reached at kconti@globe.com. Follow her on Twitter @GlobeKConti.