Expert consulted: 
You've cleared the table and loaded the plates, but the dishwasher is only half-full. Running it now feels wasteful, and leaving it until tomorrow feels a little gross. So which is it?
The good news is that waiting until morning is no big deal. ‘It’s generally fine to leave dirty dishes in the dishwasher overnight, especially if you've just loaded them after dinner,’ says Noah Pinsonnault, reviews analyst in the Good Housekeeping Institute's Home Care & Cleaning Lab.
The trouble starts when one night stretches into several.
Why you shouldn’t let dirty dishes sit for days
‘The dishwasher makes a poor long-term storage cabinet for unwashed dishes,’ Noah says. Food residue left in a closed, damp appliance can encourage bacteria and mould to grow, and it can quickly turn into an unpleasant smell when you open the door. Lingering scraps can also attract pests, which is the last thing you want setting up camp in your kitchen.
His rule of thumb is simple: don’t let dirty dishes sit for more than a day.
How to stop a half-full dishwasher from smelling
- Scrape, but skip the rinse. Dishes don’t need rinsing before they go in the dishwasher, Noah says, but you should always scrape off large chunks of food first.
- Use the half-load cycle. Some dishwashers come with half-load cycles which focus the wash on a section of the dishwasher. With this, you won’t have to wait until it’s full.
- Use the rinse cycle. ‘If you find that the dishwasher isn't full enough to warrant running it after dinner, the rinse cycle can help wash away food residue and prevent odours from developing,’ he says. It buys you time until you have a full load. Dishwashers are advanced enough to handle most stains without rinsing, but it can be handy where residue is particularly stubborn, smelly and dried-on.
- Run it within a day. Once you’ve got a full load, or about 24 hours have passed, start the cycle.
- Empty and clean the filter between washes. This stops food residue from getting caught and contributing to smells. You will need to deep clean the dishwasher with a dedicated cleaner every two months for the same reason.
There’s no need to feel guilty about waiting until breakfast. Just don’t treat the dishwasher like a holding pen for the whole week.
Dishwasher cleaning kit
Noah works as a product reviews analyst in the Home Care & Cleaning Lab where he helps design and perform tests on various product categories. He draws on scientific expertise garnered during his time as an environmental researcher, where he managed environmental monitoring equipment, analyzed water samples in a lab and developed protocols for restoration projects. He holds a Bachelor’s Degree in environmental science from the University of Wisconsin-Superior.
