The information watchdog is scrutinising the use of the public's private data for political purposes following concerns over an analytics firm linked to the Leave.EU campaign.
The Information Commissioner's Office (ICO) said it is assessing how data analytics impacts on data protection.
It has raised concerns about reports linking Cambridge Analytica (CA) to Leave.EU, backed by Nigel Farage.
A CA spokesman said it is compliant with UK and EU data law.
The company uses artificial intelligence to identify key voters.
On Friday, Labour MP Stephen Kinnock, who supported the Remain camp, called on the Electoral Commission to investigate allegations that Leave.EU had not declared the role of CA in its campaign.
An ICO spokeswoman said: "We have concerns about Cambridge Analytica's reported use of personal data and we are in contact with the organisation.
"We are also conducting a wider assessment of the data protection risks arising from the use of data analytics, including for political purposes, and will be contacting a range of organisations.
"We intend to publicise our findings later this year."
A CA spokesman told The Observer that it is "in touch with the ICO, and are happy to demonstrate that we are completely compliant with UK and EU data law".
Leave.EU has denied any wrongdoing and told The Guardian that CA did no work for the campaign formally.
A spokesman added: "If they had it would have been way before you had to report expenditure.".