Belvoir’s Scottish lettings businesses lost an average of £9,000 per year, per branch, after tenants’ fees were banned in late 2012.

However, Belvoir director Dorian Gonsalves said that if a ban were to be introduced south of the border, the loss per branch would be higher.

He said: “In Scotland it was already illegal to charge premiums, so there was some knowledge of tenants’ fees being banned. The law was tightened up because there had been no real definition of ‘premium’.

“Since then, offices have lost an average income of £9,000 annually, but I think it would be in excess of that in England.”

He said that in Scotland, Belvoir agents had made up the shortfall through a variety of means, including charging landlords higher fees.

The landlords would have passed these costs on to tenants in the form of higher rents – with rents having gone up across Scotland.

Both Labour and the Green Party have made manifesto commitments to ban letting agent fees charged to tenants.

Shelter is campaigning for a ban, and Citizens Advice has also called for one.