The trade body's latest Housing Insight report found that the average number of homes available to rent at each member branch fell slightly to 11.25 during June 2026. This came as agents registered an average of 96 prospective tenants per branch.
Despite the imbalance between supply and demand, there are signs that landlords may have less scope to push rents higher.
Propertymark found that 63% of member agents reported rents remaining broadly unchanged during June, while 29% reported increases and 8% saw rents fall.
Official figures included in the report show that average UK rents were 3.3% higher than a year earlier and increased by 0.3% between May and June.
Average monthly rents reached £1,442 in England, £1,012 in Scotland and £843 in Wales.
There was also a slight increase in rental arrears reported by Propertymark members, with the figure reaching 2.3% in June.
Void periods present another potential concern for landlords. The average period between tenancies increased to just over three weeks in June, despite the continued imbalance between tenant demand and the number of properties available.
The number of new tenancies agreed also fell slightly, with member branches recording an average of 8.15 during the month.
Propertymark members reported signs of tenants becoming more price sensitive in some areas. An agent in Kent said: "Rental market prices are coming down, with tenants walking away if the landlord will not accept the reduced offer price."
However, an agent in Surrey reported a different experience: "Better quality of tenant, some finding rents too much, but most accepting of rent increases and the overall increase in rents."
The report also highlighted the impact of the Renters' Rights Act on the market, with agents in the South West and East of England reporting that changes to notice periods were affecting when some tenants could move between properties.
Phil Spencer, founder of Move iQ, said: "June’s figures show a housing market that is still moving, but where buyers and renters remain cautious. Buyer registrations dipped, while viewings and sales agreed stayed broadly steady, highlighting that demand hasn’t disappeared but buyers are increasingly selective and realistic pricing remains crucial.
"Although inflation is moving closer to target and the Bank Rate has held steady, affordability remains a significant concern, with 31% of adults reporting difficulty meeting their rent or mortgage costs.
"In lettings, demand continues to significantly outstrip supply, although longer void periods and reports of rents easing in some areas suggest a more nuanced market.
"As we enter the second half of the year, economic conditions and the Autumn Budget will be important factors. Realistic expectations will remain key for buyers, sellers, landlords and tenants."
