Property portal Residential People has accused Rightmove of charging agents too much.
The company said Rightmove, which is the market leader, charges crippling fees that put a significant squeeze on independent agents.
Rightmove angered agents in November by hiking fees, as costs for single-branch agencies vary from £1,936+VAT down to 990+VAT.
Christopher May, director of Residential People, said: “As it stands, property portals make money by charging agencies to list on their site, regardless of a sale or let being made.
“Depending on the quality of your listings, brand notoriety, area of operation, and a whole host of other factors, you could end up paying a considerable fortune to a portal before you even generate your first lead.
“Property portals are undoubtedly a main driving force for the industry and are platforms that are here to stay, but what good is a portal without the agents supplying the properties?
“In theory, portals should work for the agent, not against them, yet in practice, this rarely is the case.”
Residential People is a free-to-list platform that delivers income using features it said were ‘optional’.
The company will charge for exclusive annual advertiing for agents, a marketing suite of products, property services advertising for brand awareness, new features like a discount property section, and for its businesses for sale section.
The company hasn’t been involved in the UK market for long, but has 1 million listings worldwide.
Rightmove was approached for comment.