Why You Should Never Use A Dishwasher Tablet In Your Washing Machine

Depending on what you find on the internet in general and social media in particular, that information can either be a source of tips and hacks with the potential to make life that much easier — or it can create extra work when the tip and/or hack fails. 

As Consumer Reports points out, some of these viral hacks actually work, like cleaning your shower with a dishwashing wand (works, under some conditions) and using a baking soda and vinegar paste on your glass cooktop (also works but conditions apply). But there are a few you may not want to try, such as "cleaning" your furniture with Pine-Sol that's been warmed over (hard pass, says CR).

To the latter we can now add a cleaning hack that 7News claimed in 2021  "took Australia by storm." The cleaning hack involved using dishwasher tablets to clean out a dirty washing machine. The news site quotes an unnamed washing machine technician as saying using one tablet every two weeks would keep the appliance clean, but the report also adds that "hundreds of mums" have instead said using "four tablets on a hot cycle" would give a washing machine owner "the best results by far."

Appliance manufacturers aren't keen on the hack

And while 7NEWS Australia also showed photos of the water that emerged from the washing machine after it had been cleaned with the dishwashing tablet, appliance experts have since come forward to weigh in on the hack — and their verdict has been to give it a miss. 

One spokesperson for New Zealand appliance maker Fisher & Paykel told 9Now that even though the dishwasher tablets might be able to clean out the guts of a dirty washing machine, the tablets could also leave a coating in the drum that might not be kind to your clothing. 

Perhaps it could be seen as a further cause for concern when leading appliance maker Bosch actively discouraged its machine owners from using dishwasher tablets — either to clean the washing machine itself, or to do the laundry with. Instead, Bosch recommended its own brand of washer cleaners as well as descalers, saying that special washer cleaners would actually help "maintain the efficient performance of your machine." As an alternative, you might want to consider a homemade solution of vinegar and a bit of dish soap, which may do the trick instead.

Cleaning agents are formulated differently

While you could argue that dishwashing detergent and laundry soap are both meant to clean things, the University of Wisconsin-Madison says the two are not interchangeable because of the way the cleaning agents are formulated. UWM chemistry lecturer Allen Clauss, who once worked at Procter & Gamble, says dishwashing detergents deal with grease and food stains because they have high pH and contain an amount of chlorine. He also adds, "[Dishwashing liquids are] a great way to clean your dishes, but it's not something you want to put your hands into."

And even though traditional powdered laundry soaps may seem similar if not identical to dishwashing liquid, the two aren't the same because the former tends to use other types of formulations — as well as what UWM described as "brute force" to deal with dirt and grease.

Australian expert Ashley Iredale further tells 9Now that while the plan might work "initially," the dishwasher-tablet hack isn't something he would recommend, adding that "washing machines aren't designed to deal with highly caustic dishwasher detergents, so doing this may damage seals and hoses over time — which could also void your consumer guarantee or warranty as the manufacturer may say you didn't follow proper instructions."