Four companies have been fined a total of £370,000 after flouting data laws to “aggressively pester” people with hundreds of thousands of nuisance phone calls.

According to the Information Commissioner’s Office (ICO), the companies were motivated “solely” by profit as they attempted to sell home insulation to those who had opted out of marketing calls.

Andy Curry, the watchdog’s investigations head, said the practice had left vulnerable people, including the terminally ill, “distressed, upset, worried and inconvenienced”.

All those who complained to the ICO were registered with the Telephone Preference Service (TPS), a statutory register of people who have said they do not want to receive calls.

Posh Windows UK Limited, which is based in Stoke-on-Trent, made 461,062 calls to those registered with the TPS between August 2020 and April 2021.

The company, which was fined £150,000, told the ICO that it complied with marketing laws, but its responses were deemed “vague, evasive and contradictory”.

Eco Spray Insulations Limited from Eastleigh, Hampshire, made 178,190 calls without screening against the TPS register and was fined £100,000.

Euroseal Windows Limited, based in Newcastle-under-Lyme, made 169,830 calls in 2020.

Having “deliberately made the calls to generate income”, it was handed an £80,000 penalty and an enforcement notice.

Green Logic UK Ltd from Derby, which made 11,825 calls in 2020, was also given an enforcement notice plus a £40,000 fine.

Along with failing to engage with the ICO, its calls were found to be “misleading and persistent, and all made for financial gain”.

Mr Curry said: “The complaints we received showed that people were distressed, upset, worried and inconvenienced by the calls.

“For people to feel this way, in their own homes where they should feel safe, is unacceptable.

“These companies all aggressively pestered people, including some vulnerable individuals, forcibly trying to make them buy products that they didn’t need or want.

“All of the calls were driven solely by the companies’ wish to make financial gain.”