The centre is believed to be using automated dialling technology to contact 90 million numbers.
The company is said to be offering to consolidate debts or make claims for mis-sold payment protection insurance.
People were not able to opt out of the recorded messages, which were unsoliciticed and from different numbers.
David Clancy, ICO enforcement team manager said: “It is astounding to think this one small company has the ability to pester millions of people with unwanted calls on a huge scale.
“Thanks to this raid we have seized information that will enable us to discover where this organisation is sourcing their data and prevent them from selling it to third parties.
“The rules on making recorded messages are clear, and if the evidence proves the law has been broken we will act.”
The ICO has removed documents and computer equipment as part of the investigation.
The public body is weighing up whether to take action against the company.
