Even as the state began to slowly ramp up its COVID-19 vaccines last month and an the coming end of the pandemic became a little more believable, many homeowners still were reluctant to list.

Statewide, new listings for single-family homes were down 17.1 percent in January on a year-over-year basis, according to new figures released by the Massachusetts Association of Realtors. At the same time, a substantial increase in the number of new condominium listings in Greater Boston helped send an increase in the number of new listings inching upwards by 3.2 percent compared to last January.

“January started 2021 off strong for the housing market in Massachusetts. Inventory constraints continue to persist, but we are hopeful that an active year for new construction and an increase in spring home sellers will bring more opportunities for buyers,” Steve Medeiros, 2021 MAR president and a Keller Williams Realty Realtor, said in a statement.

Market-watchers have been predicting that 2020’s red-hot real estate market, driven by a dramatic increase in demand and a pandemic-fueled decrease in listings, will continue through 2021 until increasing COVID-19 vaccination rates encourage more homeowners to sell.

Realtor associations covering much of Southeast and Central Massachusetts saw new single-family listings off by nearly 20 percent, but the biggest year-over-year decline was seen on Cape Cod, with new single-family listings off by 42.2 percent, with only 271 single-family homes on the market across the entire peninsula. The five-county Greater Boston region saw a 5.5 percent year-over-year decline in single-family listings in January and the Pioneer Valley both saw new listings drop by 10.8 percent, meaning 1,701 and 389 houses were on the market in each area, respectively.

“We continue to struggle with a limited inventory of homes to sell, and sellers are reaping the benefits.  It’s all about supply and demand, and with more buyers than listings that’s putting upward pressure on prices,” Greater Boston Association of Realtors President Dino Confalone said in a statement.

The listings shortage will continue to put pressure on single-family prices, he added, with more than a few homeowners ready to sell but holding off out of fear they won’t be able to find a new home.

“The start of each year typically brings a lot of anticipation about the approaching spring market and that’s especially true now given all we went through in 2020,” Confalone, an agent with Gibson Sotheby’s International Realty in Cambridge, said.  “There are so many buyers who have been house-hunting for months, if not years, and that’s created tremendous pent-up demand. When you combine that with those now looking to trade-up for more home or to take advantage of historically low mortgage rates, you get a busier than normal market.  That’s exactly what we’ve seen, with large crowds at open houses, plenty of multiple offer situations, and homes priced right selling quickly.”

The condominium market in the Boston area appears to be avoiding the same pains that look set to plague the single-family side, however.

Within the GBAR coverage area, the number of new condominium listings jumped 15.2 percent in January on a year-over-year basis, to 1,154. In the larger five-county area, the number of listings dropped only slightly, by 2 percent, to 1,619. The bulk of the increase in condo listings is concentrated in Suffolk (587 new listings, a 24.4 percent increase) and Norfolk (246 new listings, a 40.6 percent increase) counties.

“We’ve seen a big jump in condo listings over the last few months not just in the luxury markets of Boston and Cambridge, but in the adjacent suburbs,” Confalone said.  “With mortgage rates at records lows and inventory more plentiful, it’s created some terrific opportunities for entry-level buyers and those looking to downsize.”

An 30.7 percent year-over-year increase in pending sales in GBAR’s territory in January was a sign that some homebuyers have taken notice of the trend, the association said, echoing statements by other market-watchers earlier this year.