Demand has fallen by over a third, the NAEA has reported.
It says that last month, demand was down 35% on July last year, and that it is at its lowest since November 2013.
Applicants per branch dropped to 298 from an average of 330 in June. Last July, the number of applicants per branch was 462.
At the same time, the average number of available sales properties per branch rose from 37 in June to 38.
The NAEA also says that the number of sales to first-time buyers was down 5% on June, and that eight out of ten properties sold for under their asking price.
In July, the number of sales agreed per member branch remained at eight.
A third (31%) of estate agents reported that there has been no changes in the housing market since Brexit and everything is business as usual.
Mark Hayward, NAEA managing director, said: “We expected to see uncertainty in the immediate period following Brexit and during the summer months the market always quietens down, so we are optimistic that the housing market will spring back into full swing in the coming months.”