The number of sales agreed also increased, from an average of eight per branch to nine. This suggests that the increase in sellers reflected confidence in the market rather than a glut of unsold properties.
The percentage of sales to First Time Buyers (FTBs) decreased slightly from 24% in May to 20% in June.
President of the NAEA Wendy Evans-Scott said: "The leap in available housing stock suggests increased confidence amongst sellers. They think there is a much better chance that their home will sell. For house-hunters, this is welcome news as it offers a wider choice of properties to pick from.
"However, efforts are still required to assist those looking to get onto the housing ladder if we are to see buyer activity match that on the sale side."
During June, the number of house-hunters entering the market dropped for a third consecutive month. In June 263 people registered per branch, compared with 275 in May; a decrease of 4%.
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