More than one in 40 homes in Sussex lies unoccupied despite the number of empty properties dropping in the past year.

In total 20,000 homes currently lie empty, according to the latest figures by charity Homes From Empty Homes based on council tax returns.

More than a quarter of these homes have been empty for more than six months – the equivalent of one in 130 homes.

Hastings had the highest proportion of empty homes at one in 25, while Brighton and Hove also scored highly with one in 30 – or more than 3,800 homes.

The number of empty properties has declined by 1,800 across the county since last year’s report but Arun, Adur, Horsham, Lewes, Mid Sussex, Wealden and Worthing all saw increases in the number of long-term empty homes.

The reduction has been credited in part with a recent change in the law meaning empty homes are no longer automatically exempt from council tax for the first six months while councils can charge a higher level of council tax on homes that had been empty for more than two years.

The continuing growth housing market has also made it more viable for property owners to renovate some derelict houses.

Phil Graves, of Brighton-based estate agents Graves Jenkins, said that he anticipated that part of the empty homes figure would “churn” as people moved houses, another proportion would be homes on sites set for redevelopment while properties above pubs and shops not lived in by owners but used as storage would account for some more.

Councillor Bill Randall, chair of Brighton and Hove City Council’s housing committee, said the authority’s success in returning more than 150 private sector empty properties per year was the “envy” of similar authorities nationally.

He added: “The higher proportion overall of empty properties in Brighton and Hove compared to the rest of Sussex is not surprising because around 30% of properties in the city are privately rented, double the national average, and have a high turnover rate.”

A Hastings Borough Council spokesman said the authority had almost double the level of pre-1919 housing stock, meaning repair bills were likely to be higher, while lower rents meant there was a smaller return on that investment.

Councillor Christopher Snowling, cabinet member for health and community, said that some of the increase was due to affordable sheltered housing currently undergoing recent redevelopment and new private developments.

A Wealden District Council spokesman also said that some of the empty properties were bedsits in sheltered accommodation which have now been decommissioned ahead of remodelling.