OnTheMarket has announced a new monthly record of 25.4m visits.
The figure, for May, was up on the previous record high of 23.5m visits in January.
OTM also announced a record level of leads for agents, up 15% on January.
The company, in a statement to the stock exchange, also said that OTM now has over 650,000 listings – about 65% of Rightmove’s stock, and over 83% of Zoopla’s.
OTM says it sent over 100m property alert emails during May.
CEO Ian Springett said in the statement: “Our May performance is further evidence that our growth strategy is working.
“We have delivered another set of record-breaking traffic and leads results for our estate and letting agent customers, many of whom are choosing to list their properties on a ‘New & exclusive’ basis.
“This is driving traffic to our portal while injecting competition into a market which was previously a ‘duopoly’.
“The high volume of instant alert emails now being sent each month shows how our engagement with active property-seekers and the value we deliver to agents are both continuing to grow strongly.”
The latest statement made no reference to agency numbers but a spokesperson said there had been no update since February 5, when OTM said it had over 12,000 contracted offices.
Meanwhile, OTM has appointed a joint broker.
Shore Capital Stockbrokers will be joint broker alongside Zeus Capital.
The appointment followed the acquisition of OTM’s previous broker, Stockdale Securities, by Shore Capital.
OTM is due to release its annual results on Thursday.