Which constituencies are being targeted the most by online political adverts?

When Nigel Farage announced his candidacy, he boasted: "We haven't spent a bean on Facebook pushes or advertising."

But the data shows Reform has, in fact, spent a significant number of beans.

More than £3,800 has been spent by the party's candidate in Great Yarmouth, on more than 50 Facebook and Instagram adverts since the election was called on 22 May.

Because tech platforms like Meta and Google publish regular updates to political advertising spending, it's possible to track which constituencies campaigns are pouring money into. Sky News, in partnership with Who Targets Me, which tracks digital political adverts, can reveal the key battlegrounds so far.

Hendon, Rochester and Strood, Welwyn Hatfield and Croydon South in Greater London and the home counties, and Rossendale and Darwen in Lancashire, are the places with the biggest ad spend from multiple advertisers - the constituencies where different parties are spending the most to try to swing the election for their candidate.

Hendon tops the list with £26,138 being spent by all parties up until 2 June.

But with different budgets for each party, the amount being spent varies significantly, from hundreds, to thousands, of pounds.

From 22 May to 1 June, Labour has poured the most money into Dover and Deal, with the local candidate spending £19,200.

Hendon has seen the highest Conservative spend, with £25,483 forked out by the local party candidate.

'I've been bombarded with adverts'

Ynys Mon has been another popular place for Tory money, with the party's candidate spending more than £10,000 on online adverts in the week leading up to 2 June.

Katie Hayward, an award-winning beekeeper in Anglesey (the constituency of Ynys Mon) says she has been bombarded with the ensuing ads and has stopped checking her social media account as a result.

"In the last three weeks. I literally couldn't go a minute without seeing the MP's face telling me how wonderful she was, and it must have cost a fortune. But I got to the point where I don't want to check my Facebook," she said.

"I've just ended up switching off my social media and not being able to look at it because it's physically made me sick."

However, Kate Dommett, a professor of digital politics at the University of Sheffield, said "most people really don't pay that much attention to politics" and this could pose a real challenge to the parties.

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She added: "We're also seeing them turn to more digital media than ever before to use both organic content, but also these paid adverts to really try and get their message across.

"They're consistently generating content that they can try and maximize the chance that ordinary people will pay attention to what they're saying."

Where else are parties targeting?

A smaller party with a smaller budget, the Liberal Democrat candidate in Whitney has spent £2,345 on political advertising.

But the Green Party has spent thousands trying to shore up a win in Bristol Central. No adverts are currently active, according to Meta, but it ran two versions of its most popular ad, which featured Keir Starmer, and reached approximately 30,000 people and cost it up to £4,500. Data shows it targeted under-35s the most.

Amelia Jacob, co-editor of Bristol University's student newspaper Epigram, said: "It's mainly on Instagram and Twitter I've seen more adverts for the Greens."

"I've really noticed an increase since the election was called - but it hasn't reached the level of feeling like spamming," the 22-year-old said.

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Sam Jeffers, executive director of Who Targets Me, says it's extraordinary that the Greens have targeted such a small constituency with the biggest social media spend in the country.

But with the main Green candidate standing down in Brighton, the Greens need an MP and are doing what they can to ensure that happens.

"Bristol has a lot of green councillors and has been a long-term target for the Green Party. So, this is the most sensible place to spend," Mr Jeffers said.

For the SNP, its candidate in West Aberdeenshire and Kincardine attracted the most money - but at £392, this is significantly less than what other parties have spent.

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Plaid Cymru had a similar small spend, putting £366 into three online adverts in Ceredigion Preseli.

The types of adverts being seen on Facebook, specifically, is "very static," said Professor Dommett, compared to more creative attempts on TikTok (which does not allow paid political advertising).

"Videos of parliament, videos of politicians - there doesn't seem to be a huge amount that is trying to grab attention," she said.

The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories. We combine traditional reporting skills with advanced analysis of satellite images, social media and other open source information. Through multimedia storytelling we aim to better explain the world while also showing how our journalism is done.