The short answer
For most workplaces with more than a handful of staff, a plumbed-in system works out cheaper within the first year, takes up less space, and removes the ongoing admin of bottle deliveries. Bottled coolers still make sense in a small number of situations, mainly sites with no practical access to a mains water supply.
How the costs compare
With a bottled cooler, you pay for the water itself, typically per 19-litre bottle, plus delivery and often a rental charge for the unit. A busy office can get through several bottles a week, and the per-litre cost adds up quickly. There is also a hidden cost in staff time: taking deliveries, storing bottles, and lifting them onto the machine.
A plumbed-in cooler or filtered tap connects directly to your mains supply. After installation, you pay for mains water (a fraction of a penny per litre), scheduled filter changes and servicing. Usage is effectively unlimited, so the cost per litre falls the more your team drinks. For most sites, the crossover point where plumbed-in becomes the cheaper option arrives within months, not years.
Hygiene and water quality
Bottled coolers introduce two hygiene considerations that plumbed-in systems avoid. First, every bottle change is a chance for airborne contamination as the new bottle is seated. Second, bottles in storage need to be kept cool and out of sunlight, which is not always practical in a busy stockroom.
A plumbed-in system draws from the mains, which in the UK is already tightly regulated, then passes the water through filtration to improve taste and remove chlorine, sediment and other impurities. With filters changed on schedule and the unit sanitised at each service visit, water quality stays consistent all year round. As a WHA member, we service every system we install to the association's standards.
Space and practicality
Bottle storage is the cost nobody budgets for. A stack of full and empty 19-litre bottles takes up real floor space, and someone has to manage the rotation. Plumbed-in units need only their own footprint, and countertop and under-sink options mean even small kitchens can usually accommodate one.
Sustainability
Even where bottles are collected and reused, bottled water carries the footprint of trucking heavy loads of water around the country. A plumbed-in system uses water that is already piped to your building, cutting delivery mileage out of the picture entirely and removing single-use plastics where staff would otherwise turn to shop-bought bottles.
When bottled still makes sense
To be fair to the bottled option: if your site has no accessible mains supply near where people gather, or you need a temporary solution for a short-term site, bottled coolers do the job. For everything else, plumbed-in wins on cost, hygiene and convenience.
What to do next
The right system depends on your headcount, layout and existing plumbing, which is why we always start with a free site survey. We will look at where a unit could go, what the installation involves and give you a clear, tailored quote with no obligation.