EVERETT — Snohomish County's real estate market validated the law of supply and demand in 2012, with weak inventory and willing buyers adding up to higher prices for sellers.

It was the first year since 2007, when the recession started, that prices increased from the prior year. However, the average combined sales price of $265,920 for single-family homes and condos in 2012 was still $6,301 below the average sales price of $272,221 reported in 2004, according to data from the Northwest Multiple Listing Service.

NWMLS members reported 10,631 closed sales of single-family homes and condominiums in Snohomish County during 2012, a 14.1 percent improvement over 2011's volume of 9,316 transactions.

Last year's completed sales included 8,961 single-family homes and 1,670 condominiums. Together, these sales were valued at more than $2.8 billion.

The relative lack of new listings and strong demand in Snohomish County throughout 2012 drove monthly median price increases.

Overall inventory shrank from 15,281 new listings in 2011 to 12,874 listings in 2012, the NWMLS report showed. The ratio of 27,945 active listings to 16,044 pending sales in Snohomish County last year means the supply of current listings were typically exhausted in 1.74 months. Most real estate analysts consider a supply of three to six months to be a balanced market, meaning the market favors neither buyers nor sellers.

Median sales prices in Snohomish County for home and condos combined increased by $14,900, or 6.48 percent, rising from $230,000 to $244,900. Mason, Snohomish and King counties reported the three largest increases in median prices among the 21-county NWMLS reporting area.

Single-family home prices in Snohomish County rose 7 percent, from a median of $243,000 in 2011 to $260,000 in 2012, the NWMLS reported. Median prices for condos in the county fell to $146,100 in 2012, a decline of 9.81 percent.

Other highlights:

•It was the first year average prices for homes and condos in Snohomish County posted a year-over-year increase, after peaking at $383,004 in 2007 and dropping to $255,364 in 2011.

The highest sales price for a single-family home was $3,564,000. The average was $284,288.

For the 245 new condos sold in 2012, the highest sales price was $1,222,500; the lowest was $110,000. The median price was $232,950; the average, $258,543.

New homes accounted for 1,701 sales in 2012. The most expensive was $1,330,000; the least expensive was $144,000. The median price was $214,500; the average, $327,779.

Kurt Batdorf: 425-339-3102; kbatdorf@heraldnet.com. The Herald Business Journal: www.theheraldbusinessjournal.com