Where Can I Buy Deionised Water?

by ReAgent Chemicals

Before we look at where to buy deionised water, let’s look at what it is. Deionised water is a form of purified water. It is made by running water through an electrically charged resin which switches hydrogen and hydroxide ions for dissolved minerals, before recombining to produce deionised water. The result is water that has had nearly all its mineral ions, such as chloride, sodium, and iron removed. However, it does not remove most bacteria or viruses.

Uses of deionised water include as a cooling agent in medical devices, in cleaning industrial machinery, in some aquariums, window cleaning and in cosmetics.

Buying Deionised Water

You can buy deionised water at a wide range of places.  Naturally, we are going to suggest ReAgent as being one of the most suitable, but it would be a bit misleading if we were to only suggest ourselves!

There are certain customers, different business needs and certain situations where we won’t be the most suitable supplier, so in the interests of transparency we will mention some alternatives as well.

Buying Deionised Water from a Chemical Manufacturer

If you are a business looking for an established, reputable chemical manufacturer, a company like ReAgent is probably what you’re looking for. Why?

Reliability is especially important and is our top priority – you wouldn’t want to order 20,000 litres of deionised water for pressure-testing a vessel as part of a large building project only for it to be late or out of spec, as it could delay the project at considerable cost. We ensure that doesn’t happen. Additionally:

  • An established company means a proven track record, with thousands of satisfied customers (ReAgent was established in 1977)
  • We are experts in this area and supply many different types of water
  • We offer advice on the best water for you: it may well be that another type of purified water is more suitable for your needs
  • We offer free pre-purchase technical support as well as after sales support
  • We have various quality accreditations including ISO 9001 and ISO 14000
  • We guarantee our water will meet specificationyou can find our deionised water specs here
  • We use reliable couriers which maximises the chances of your order being delivered on time and in full
  • We can provide certificates of conformity and certificates of analysis if required (these may incur additional cost, depending on the size of your order)
  • We can make to order, which means quality is likely be higher than alternative sources
  • We offer accounts for customers who will buy regularly

However, at ReAgent we don’t supply deionised water direct to consumers.

Deionised Water for Consumer Purchase

Deionised water is available for consumer purchase at many large supermarkets, hardware stores and of course from online retailers such as Amazon and eBay. There are definitely benefits to this – it’s generally cheaper, you can pick some up with your weekly shop, and it’s perfectly fine to use for filling up your iron or in your car battery.

However, as it’s not made to order the quality and conductivity probably won’t be as good, and it’s only really suitable for purchasing a couple of packs of less than 25 litres.

If you’re buying from Amazon or eBay, check the sellers carefully as they are generally less reputable than established chemical suppliers – they won’t have the same quality accreditations, for example.

Online purchase also introduces another party to the supply chain, which can complicate matters. For example, it can be difficult to obtain a VAT receipt for your purchase. There’s also potentially limited after sales support.

Make Your Own Deionised Water

And there’s another alternative. You could make your own deionised water. Small, countertop distillers can be bought if you only need a small amount of high purity water, and could be the best option if you need a small amount every now and then.

It also means you can make it as and when you need it. Just be mindful that the output is normally small and you’ll consume a relatively large energy compared to the amount of water produced.

Advice on the best way to buy deionised water

For comprehensive information about deionised water, check out our Complete Guide to Deionised Water resource.

If you’re a business wanting to purchase deionised water at scale, you can do so online or by calling us on 0800 990 3258.


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