The anchor move: £190 million into Slough
Mars has committed £190 million to overhaul its Slough factory in the United Kingdom, the site where the Mars bar was first made in 1932 and where Galaxy and Maltesers are still produced today. The investment runs from 2023 through 2028, per Food Business News, and will bring in robotics, AI, upgraded machinery, advanced cooling systems, and energy-efficient utilities.
The headline technology is digital twin: AI-driven virtual models of the factory floor that allow Mars to simulate and adjust production in real time. The stated goals are tighter process control, better consistency across product lines, and lower waste. These are not abstract targets. In a high-volume chocolate plant, small improvements in yield and energy use compound quickly across millions of bars. Mars has not published specific waste or cost-reduction targets for the project, so you should treat those outcomes as directional rather than guaranteed.
The Slough commitment also sits inside a broader European capital deployment story. Mars unveiled a €1 billion European Union investment program the year before the Slough announcement, according to ConfectioneryNews. Slough is one node in that network, not a one-off project.
Why this is happening now
Two pressures are running in parallel. First, cocoa costs remain elevated and volatile, so improving plant efficiency is one of the few levers Mars can pull on the cost side without changing its recipes. Second, the Kellanova acquisition at the end of last year added a large new manufacturing footprint to the Mars network. That $36 billion deal, flagged by ConfectioneryNews, brought in Pringles, Pop-Tarts, and Cheez-It, brands that sit in snacking categories with different manufacturing profiles from chocolate. Upgrading existing plants while absorbing Kellanova's facilities is a significant operational challenge. The Slough investment signals that Mars is choosing to modernize heritage sites rather than consolidate away from them.
The cocoa-free pilot: a raw-material hedge
Separately, Mars is running a limited test of cocoa-free chocolate at Rewe supermarkets in Germany, selling from April to October 2026. The product, a Balisto Trail Mix, uses ChoViva, an ingredient made from fermented sunflower seeds by German start-up Planet A Foods. Per FoodNavigator, Planet A Foods has also secured contracts with Barry Callebaut and Nestlé, so Mars is joining an emerging supplier relationship rather than going it alone.
The pilot structure, exclusive to one retailer, limited to one market, and time-boxed to six months, is a deliberate risk-management design. Mars can read real consumer response before committing to a permanent rollout or broader sourcing change. For your planning purposes, this is not a signal that Mars is abandoning cocoa. It is a signal that Mars wants the option to diversify if cocoa costs or availability make that necessary.
What the Kellanova acquisition adds to the footprint
The Kellanova deal is the biggest single change to the Mars manufacturing and supply-chain footprint in recent memory. ConfectioneryNews describes the acquisition as significantly broadening Mars' reach beyond confectionery into global snacking staples, following a pattern set by the Wrigley acquisition in 2008 and the Trü Frü acquisition in 2022. Each of those deals added new raw-material dependencies, new co-manufacturing relationships, and new logistics networks. Kellanova is the largest of the three.
The integration is still early. Mars has not published a detailed Kellanova supply-chain roadmap in the available signals, so the specific sourcing shifts, plant rationalization decisions, and logistics partner changes that will follow are not yet visible from the outside.
The packaging risk sitting in the background
One supply-chain risk Mars shares with the rest of the industry is packaging. Naphtha, a petroleum-derived chemical used in the inks, films, coatings, and adhesives that flexible food packaging requires, is under supply pressure because of geopolitical disruption in the Middle East. Japanese snack maker Calbee temporarily switched 14 products to black-and-white packaging because of naphtha shortages, per FoodNavigator via BakeryAndSnacks. Mars relies on the same packaging substrate for brands like M&Ms, Skittles, and Pringles. The Slough investment in energy-efficient utilities may help on the energy side, but it does not address packaging input risk directly.
What competitors are doing
Ferrero is investing in brand rather than plant right now, launching a Wonka product family tied to a Netflix partnership and spanning chocolate, sugar confectionery, ice cream, and cereals, per ConfectioneryNews. That is a different capital allocation bet: demand creation over supply-chain hardening. Toms Group, the Danish maker, is chasing low single-digit growth and managing cocoa volatility through flavor and texture innovation rather than capital investment, per Just Food. Neither competitor is making the kind of manufacturing capital commitments Mars is making right now.
What to watch next
Three things will tell you whether Mars' supply-chain bets are working. First, watch whether the Rewe cocoa-free pilot extends beyond October 2026 or expands to other markets. A rollout decision would signal that Mars sees ChoViva as a genuine procurement option, not just a proof of concept. Second, watch for any public communication about Kellanova plant rationalization. A company that just spent $36 billion on an acquisition and £190 million on a UK factory upgrade is managing a complex integration; any signal of closures or consolidation in the Kellanova network would reshape the supply picture. Third, watch packaging input costs. If naphtha disruption deepens, every confectionery and snacking brand with coloured flexible packaging faces a constraint Mars cannot solve with factory automation alone.