Mars powers production growth with $253.6m smart factory investment

Mars smart factory investment overview

• Mars invests £190m to transform Slough into smart manufacturing hub
• Upgrades boost production capacity using AI robotics and digital twins
• Investment supports post-Kellanova integration and scalable global supply
• Strategy prioritises fewer advanced factories for efficiency resilience sustainability
• Mars reinforces UK manufacturing leadership while modernising heritage operations

The world’s biggest confectionery company, Mars, Inc. has unveiled major new plans for growth, following its merger with Kellanova in December 2025.

The American multinational, known for big-name brands including Snickers, Twix, Skittles, and of course Mars, has unveiled £190m ($253.6m) plans to transform one of its most historic factories – Slough, UK – into a next-generation manufacturing hub.

Mars says the investment reinforces the “UK’s strategic importance” to the business.

“This investment reflects our confidence in the UK as a hub to manufacture and innovate,” says Adam Grant, general manager for Mars Snacking UKI. “In taking a long-term view, we are ensuring our operations remain world-class, competitive and fit for the future.”

Birthplace of Mars

Established in 1932 by Forrest Mars, the Slough factory is the birthplace of the iconic Mars bar and remains its home, alongside other flagship brands, including Galaxy and Maltesers.

As well as supplying the UK market – one of its strongest and most important – the site also produces confectionery for distribution to Ireland and the Netherlands.

Moreover, it serves as an important part of the local economy, employing more than 1,850 people and supporting multiple generations of families.

“Our Slough factory is deeply rooted in our heritage, and as a proud family-owned business, we are committed to investing in a future that creates lasting, positive impact for the communities in which we operate,” says Mars’ Grant.

Mars says the investment will introduce “state-of-the-art manufacturing capabilities” to the site, combining robotics and AI with upgraded machinery, as well as advanced cooling systems and energy-efficient utilities to improve performance and sustainability.

Engineering innovations

As part of the upgrades, Mars will leverage its engineering and intelligent technologies to deploy digital twin technology to the Slough factory, using AI-driven data to optimise production. This will enable precise process control, consistency and uniformity across product lines, while enabling real-time decision-making on the factory floor, and reducing waste.

The investment will support extensive workforce upskilling, creating new progression routes into advanced engineering, automation, data and AI-enabled manufacturing roles, and ensuring associates have the skills needed for the future of manufacturing and engineering.

“This £190m investment by Mars is a strong vote of confidence in the UK as a place to manufacture and innovate", says UK Business and Trade Secretary, Peter Kyle. “For nearly a century, the Slough factory has produced some of the world’s best‑loved brands, and this investment shows global businesses continuing to back British skills, workers and industry.”

Mars investment commitment

The investment forms part of Mars’ broader commitment to strengthening its UK manufacturing, innovation footprint, and network of 10,000 associates.

This includes the £350m investment in the DHL Gateway in London, which removed more than one million transportation miles a year from UK roads, and the transformation of its Birstall Research & Development location, where Mars has invested £1.2m in a state-of-the-art Innovation Hub.

On a global scale, Mars’ long-term manufacturing strategy is focused on building modern, resilient and innovative production capabilities. This includes plans to invest €1bn across the EU, and a further $2bn in manufacturing in the US throughout 2026.

Mars future

This investment sharpens Mars’ manufacturing strategy at a critical moment of expansion, following its acquisition of Kellanova.

By upgrading its Slough factory into a high-output, technology-driven site, the company is effectively increasing capacity while improving precision and efficiency – enabling it to produce more, faster, and with less waste.

By doubling down on manufacturing as a source of competitive advantage, rather than outsourcing complexity, it is bringing more capability in-house, using technology to boost output, resilience and cost control.