When we think about industries driving carbon emissions, we tend to focus on transport, energy, and heavy industry; PR and digital marketing rarely make the list. But digital marketing - the online campaigns, PR strategies, and content we produce every day has a significant environmental impact. 

Research shows that digital marketing now produces more carbon emissions than aviation. Data centres, which power everything from websites to social media and digital ads, account for 2.5 per cent of global CO2 emissions - more than the entire aviation industry at 2.1 per cent. And as the internet grows, so does its footprint. 

The internet can feel intangible, but every email, ad impression, and press release requires energy, produced from burning coal, renewable energy, or another source. Data is stored and processed in vast server farms that need electricity to run and cool. 

Impressions

A single online ad campaign delivering one million impressions generates the same carbon emissions as a round trip flight from Boston to London. 

PR is also part of the ecosystem. Email outreach, online news distribution, and website traffic all add up. Research from OVO Energy found that if every adult in the UK sent one fewer “thank you” email a day, it would save 16,433 tonnes of carbon a year - the equivalent of 81,142 flights to Madrid!

In response, some businesses are trying to make digital marketing “greener” by switching to renewable-powered hosting, compressing files, or optimising ad targeting. These are good steps, but they only address part of the issue. 

The bigger question is, how much digital content do we actually need? The advertising industry thrives on volume - millions of impressions, clicks, and engagement. But more isn’t always better. 

Engaged

Many digital ads are wasted impressions, served to people who ignore them. PR strategies often rely on mass outreach, hoping a handful of journalists will respond. All of this creates unnecessary digital traffic, and, in turn, unnecessary emissions. 

This is where digital marketing intersects with the concerns raised by Badvertising, the campaign that highlights how advertising drives environmental harm. While Badvertising focuses on the promotion of fossil fuels and high-carbon products, the issue goes beyond what is being advertised. The sheer scale of digital marketing itself has an enormous environmental cost. 

Take programmatic advertising, which automates ad placements across thousands of websites. This process involves multiple data exchanges, real-time bidding, and tracking - each step consuming energy. Studies show that up to 70 per cent of programmatic ad spend is wasted on ads that are never seen by a real person. That’s a lot of energy spent for no impact. 

Instead of focusing only on efficiency, businesses need to rethink their approach to digital marketing. The goal shouldn’t be to reach the highest number of people possible, but to reach the right people in the most effective way. 

For PR, this means prioritising quality over quantity - targeted, well-researched media outreach rather than mass press release distribution. For digital advertising, it means reducing reliance on programmatic ads, focusing on engaged audiences, and limiting unnecessary tracking. It also means businesses should consider when digital marketing is truly necessary. If a campaign doesn’t add real value, maybe it shouldn’t exist at all. 

Communicate

Reducing digital carbon doesn’t mean stopping digital marketing altogether. It means making smarter choices, such as: 

• Reducing unnecessary emails - internal emails, automated follow ups, and generic newsletters add up. Cutting back saves carbon and improves engagement.
• Optimising content formats - using compressed images and lightweight videos can significantly reduce data loads.
• Choosing sustainable hosting - switching to providers powered by renewable energy can make a big difference.
• Rethinking ad targeting - prioritising high-engagement placements over mass impressions reduces waste.
• Simplifying website design - lighter pages load faster and use less energy. 

PR and marketing professionals have the power to shape public conversations about sustainability. But before we tell others to act, we need to look at our own industry’s footprint. 

The reality is, many organisations aren’t even aware of their digital carbon emissions. Measuring and addressing this impact should be as much as part of sustainability strategies as cutting waste or switching to green energy. 

Digital marketing and PR have a role to play in creating a more sustainable future. The first step is recognising that even online functions have a carbon cost. The next is making smarter, more intentional choices about how we communicate.

This Author

Emma Heley is co-founder and managing director of Thinking Hat Media, a strategic PR and content agency for global brands, start-ups and scale-ups.