Vote Leave has been fined £40,000 for sending thousands of unsolicited text messages in the run-up to the EU referendum.
The organisation sent 196,154 messages and was unable to provide evidence recipients had consented, as required by electronic marketing law.
They said Vote Leave claimed it had deleted evidence of consent relied upon to send the messages after the referendum in 2016.
ICO director of investigations Steve Eckersley said: ‘Spam texts are a real nuisance for millions of people and we will take action against organisations who disregard the law.
‘Direct marketing is not just about selling products and services, it’s also about promoting an organisation’s aims and ideals.
‘Political campaigns and parties, like any other organisations, have to comply with the law.’
It comes on the same day that Labour Leave were fined £9,000 for failing to disclose all donations to their campaign.