OnTheMarket Founder's Warning Signals Seismic Shift in Property Portals

The founder of OnTheMarket has declared that the property portal market is “on its last legs”, a striking intervention that lands precisely as speculation mounts over a potential takeover of Rightmove. For an industry that has, for the best part of two decades, been built around a handful of dominant listing platforms, this is not a throwaway remark. It is a signal that the structure underpinning how homes are bought, sold, let and marketed across the UK may be about to change fundamentally.

For professional investors and landlords, portals are not a peripheral tech curiosity — they are the plumbing of the residential and lettings markets. Every agent instruction, every buy-to-let listing, every development marketing campaign in Manchester, Birmingham, Leeds, Liverpool, Newcastle, London or Surrey ultimately funnels through one or two dominant platforms. A shake-up at the top of that chain has knock-on consequences for agent fees, marketing costs, and ultimately the speed and cost at which stock moves through regional markets. When the founder of a rival portal says the model itself is failing, investors should treat it as an early warning of structural change rather than a minor industry spat.

The context matters here. OnTheMarket was launched specifically as an agent-owned challenger to break what its founders characterised as a duopoly held by the larger incumbents. That a founder from within this challenger camp is now the one declaring the wider portal market moribund suggests the competitive dynamics have shifted again — and that consolidation, rather than fragmentation, may be the next phase. Speculation about a Rightmove takeover, as reported, only sharpens this narrative: if the dominant listing platform in the UK becomes a takeover target, it raises immediate questions about pricing power, data ownership, and how agents and landlords across every regional market will be charged for exposure to buyers and tenants.

The implications differ sharply by market participant. Buy-to-let landlords, particularly those with portfolios spread across regional cities such as Newcastle or Liverpool where yields have historically been more attractive than the London market, rely on portal visibility to keep void periods low. Any disruption to that visibility — through a merger, ownership change, or pricing shake-up — could temporarily raise marketing costs or alter which platforms deliver the best return on listing spend. First-time buyers, meanwhile, are largely insulated from the corporate manoeuvring but stand to benefit if genuine competitive disruption eventually lowers the cost base that agents pass on through fees.

Commercial investors and developers should read the situation differently again. For those marketing new-build schemes in Birmingham or Leeds, portal reach is central to absorption rates on larger developments; a consolidated or reshaped portal landscape could concentrate marketing power in fewer hands, potentially increasing costs for high-volume developer accounts even as it simplifies which platforms matter. Any credible takeover interest in Rightmove would also be watched closely by private equity and strategic acquirers assessing the broader proptech sector, given how central listing data has become to valuation models, agent software, and mortgage lead generation.

Looking ahead six to twelve months, expect three things to play out in parallel: continued speculation and possible formal approaches around Rightmove’s ownership; renewed positioning from challenger portals, including OnTheMarket, seeking to capitalise on any uncertainty at the top of the market; and closer scrutiny from agents’ bodies and regulators over concentration risk in a sector that effectively controls buyer and tenant demand flow. Landlords and developers should not wait passively — those with significant marketing spend tied to a single dominant portal would be prudent to diversify listing strategies now, before any change of ownership alters commercial terms.

The core conclusion for the UK property industry is that the portal market's apparent stability has been more fragile than widely assumed. A founder within the sector calling time on the current model, at the exact moment a takeover of the market leader is being discussed, is a rare alignment of insider commentary and market speculation. Investors, landlords and developers who treat this as background noise risk being caught out if consolidation accelerates faster than the gradual, multi-year shifts the industry has grown used to.