A ban on nuisance calls about pensions has now come into force but people are still being urged to be on their guard.

Cold-calling has been used by fraudsters trying to steal life savings or persuade people to invest in high-risk schemes.

Some 10.9 million unsolicited pension calls and messages are made a year, according to Citizens Advice.

Any firm found flouting the rules faces a fine of up to £500,000, but experts suggest fraudsters may ignore the ban.

John Glen, economic secretary to the Treasury, said: “Pension scammers are the lowest of the low.

They rob savers of their hard-earned retirement and devastate lives. We know that cold-calling is the pension scammers’ main tactic, which is why we’ve made them illegal.”

The government has faced criticism over the time taken to introduce the ban, which was first announced nearly two years ago, although restrictions on unsolicited texts and emails about pensions have already been put in place.

How do the fraudsters operate? Pension scams start with an unexpected call, text, social media approach or email – offering a free pension review, or a way to make attractive returns on pension savings.

But the money may be simply stolen or transferred into a high-risk scheme completely inappropriate for retirement savings.

Many offer eye-catching returns or high-rolling investments in hotels or green energy schemes that never materialise, or instead lead to losses.

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