Landlords are regularly overcharging new tenants by setting rents higher than legally allowed, despite new legislation introduced last July to stop the practice, according to research by RTL Nieuws.

The broadcaster monitored rental housing websites and found dozens of properties being advertised above the maximum permitted rent. In addition, landlords and letting agencies often refused to provide evidence of the number of “points” assigned to a property, which determine how much rent a property is worth.

A spot check by RTL researchers on housing website Funda turned up more than 60 properties likely to be overpriced. The points system assesses rental value using criteria such as size, value, energy label and the level of luxury.

Homes with fewer than 144 points are considered social housing and may not cost more than €900.87 per month, excluding service charges. Properties scoring between 144 and 186 points fall into the mid-market rental category, with a maximum rent of €1,184.82. Landlords are free to set rents as they wish for properties with 187 points or more.

“Landlords are trying it on,” said Mathijs ten Broeke from the tenants’ rights group Woonbond. “As long as there is a shortage [of housing], landlords will ask more than they should and there will always be people willing to pay.”

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So far, rent tribunals have reduced rents for more than 50 tenants across the country under the new rules, RTL said. In one case, a tenant in Utrecht saw their rent cut from €2,300 to €892.56 per month.

Last November, a landlord in Amsterdam was ordered to repay seven tenants more than €50,000 after wrongly claiming that a shared house was subject to “free market” rent of €4,400 per month.

However, many tenants are reluctant to take their cases to the tribunal because they fear problems with their landlords, Ten Broeke told the broadcaster. “It can be a tense step to take,” he said. “But we would recommend doing so, because you are in a very strong position if you have a rent tribunal ruling.”

Housing websites such as HousingAnywhere argue that it is up to landlords not them to make sure rents are correct and local authorities to police them.