According to the ICO, EB Associates Group made 107,003 pension calls between January and September 2019 without consent.
The firm fell on the ICO's radar during a wider investigation into organisations making pension cold calls.
It had asked lead generators to make calls on its behalf and paid up to £750 for the referrals.
The ICO concluded that EB Associates contracted the lead generators to make the calls, knowing the cold calling ban was in place, in order to try and bypass the law.
Andy Curry, head of ICO Investigations, said: “Our priority is to protect people and we will always take robust action against companies operating illegally for their own financial gain.
“Cold calls about pensions were banned to protect people from scammers trying to cheat them out of their retirement plans.
“We encourage anyone who receives an unexpected call about their pension to hang up and then report it to us.”
A ban on cold-calls in relation to pensions, which includes emails and texts, was introduced in January 2019.
The ban is enforced by the ICO, which received powers to fine bosses of companies that plague people with unsolicited cold-calls as much as £500,000.
As well as a £140,000 financial penalty, the ICO has ordered EB Associates to stop making further illegal calls about pensions or face court action.
If the Commissioner receives full payment of the monetary penalty by January 4, 2022 the penalty will reduce by 20 per cent to £112,000 but this is not available if the company chooses to appeal.
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