Tenants are now staying in one property for a record duration of 20 months, according to the latest research from the Association of Residential Letting Agents (ARLA).

This figure is up year-on-year from an average of 19 months in the first three months of 2012. It is also the joint highest tenancy length recorded by ARLA.

Well over half of ARLA agents (56.9 per cent) are seeing more tenants looking for homes than there are properties available.

According to the organisation this demand for rental properties is compounding the trend with competition for supply discouraging many existing tenants from moving, which in turn reduces the number of vacancies on the market.

At the same time, there has been a sharp drop in the number of lettings agents reporting an increase in properties coming onto the market because they can’t be sold – from 42 per cent at the end of 2012, to just 29 per cent this quarter.

Ian Potter, managing director of ARLA, said: “Our data suggested that tenants are increasingly sitting tight in their property and either reluctant, or unable to move. This stagnation means fewer and fewer properties are freed up.

“We know that many tenants renting with ARLA member agents are ‘frustrated first time buyers’ so it will be interesting to see if the recently announced Govern- ment initiatives such as ‘Help to Buy’ will impact upon these numbers.”