June was a good month for Washington-area residents who sold their houses — particularly those in the District.

New data released Wednesday show that the median sales price in the region last month rose to $440,000, which is 10 percent above the $400,000 level in June 2012.

D.C.’s median sales price soared to a record high of $529,000, according to the report by Rockville-based data firm RealEstate Business Intelligence (RBI), up $74,000 or 16.3 percent from a year ago. The jurisdiction with the highest median sales price was Falls Church, which, at $637,000, experienced a 4 percent gain from a year ago.

There was more evidence of recovery: The average amount of original list price that sellers get at the point of sale rose to 99.1 percent in June from 98.6 percent in May. It was 96.7 percent in June 2012. Moreover, the discount sellers give buyers to induce a deal dropped to 0.9 percent in June from 1.4 percent in May. It was 3.3 percent in June 2012.

“This is the first time [the original list price to sales price ratio] broke 99 since 2005. It says that it’s absolutely a seller’s market,” Corey Hart, RBI’s senior product manager, said in an interview.

Many homes in this market “are selling in nine days or less,” he added.

Inventory of single-family houses, townhomes and condos remains at near record lows — with only a 2.2 month supply. (A six-month supply is considered a balanced market.) Yet the report offers some glimmers of hope, albeit contradictory, for moderate-income and first-time buyers who for more than a year have been pushed out of the market by bidding wars: The higher sales prices appear to be encouraging more sellers to list their properties.

Year-over-year new listings rose 10.6 percent. But after increasing from March to April and April to May, they fell 15.1 percent in June. The market typically slows down in the summer months as potential buyers turn their attention to vacations.

There is an “awareness that this is a hot market,” Hart said. “Rates are still low, sellers are receiving in some areas 100 percent of list price. That’s the psychology of the market that’s playing a role” in the rise in new listings.

One factor driving the rise in sale prices is townhouses, which were the top sellers among all housing types in the region.

Demand is playing out in several ways: Sales of townhouses were at historical highs — 1,341 in the region, up 20.6 percent from June 2012. June listings were are at record lows — the supply of townhouses is at 1.4 months. The median sales price of townhouses surged more than condominiums and single-family houses — rising 12.3 percent during the past year to an all-time high of $415,000.

The average amount of original list price that townhouse sellers get at the point of sale rose to 99.95 percent in June from 99.76 percent in May, Hart said. That level was 97.71 percent in June 2012.

Meanwhile, sales of condominiums rose 15.9 percent and single-family detached houses climbed 6.7 percent, the report said.

“First-time buyers need to be on their toes,” Hart said. “It’s very competitive. Pricing is back to peak level.”

Here are the June median sales prices for several jurisdictions in the region and the percentage they rose or declined from 12 months ago:

• Arlington, $535,000, down 2.7 percent.

• Alexandria, $520,000, up 7.7 percent.

• Fairfax, $490,000, up 8.9 percent.

• Fairfax City, $465,000, up 5.8 percent.

• Montgomery, $430,000, up 4.1 percent.

• Prince George’s, $205,000, up 15.9 percent.