How Long Can You Leave Clothes in the Washer?
Wet Clothes
Wet clothes should not be left in the washing machine or dryer for more than 8 to 12 hours. After 8 to 12 hours bacteria and mildew will begin to form on the clothing, which results in bad smelling garments. Mildew forms in hot and humid environments and will cause wet clothes to smell if left idle long enough. If your dry clothes are sitting in the washing machine awaiting the next wash cycle, this will not be a problem.
This is How Long Can You Leave Clothes in the Washer.
We’ve all done it: put your dirty clothes in the washing machine, run the wash cycle, and then completely forget about the wet load of laundry until the next day.
When wet clothes are left in the washing machine or dryer for too long, they begin to smell. Why is that?
Clothes begin to smell because after 8 to 12 hours of sitting in the washing machine while wet, bacteria and mildew will begin to form. This mildew results in your clothes becoming smelly, and they will likely need to be washed again.
To avoid having clothes with mildew and bad scents, it is best to begin to drying process immediatly after the wash cycle has been completed.

How Long Can You Leave Clothes in the Washer?
Wet clothes can be left in the washer for approximately 8 to 12 hours, at which point they will begin to smell. This smell is caused by the development of bacteria and mildew, which easily grows in wet, humid environments.
If your clothes are dry while sitting in the washer, then you will not have any problems. However, wet clothes should be removed from the washer and either machine or air dried before passing the 12 hour mark. Clothes should be dried as soon as possible once the wash cycle is complete.
How Long Can You Leave Clothes in the Washer FAQ
Clothes can stay in the washer for 8 to 12 hours before they begin to smell. When wet clothes sit in the washing machine for 12 hours or more, they will start to develop bacteria and mildew, which comes with a bad scent.
If you leave wet clothes in the washing machine for more than 8 or 12 hours, you will find that the clothes have developed an undesirable smell. This smell is caused by the formation of bacteria and mildew, which easily develops in wet and humid environments.
Leaving your wet clothes in the washing machine overnight may led to the formation of bacteria, mildew, and bad smells, if the garments are untouched for 8 to 12 hours. Leaving wet clothes in the washing machine for this amount of time is not advised, and will likely result in bad smelling clothes that need to be rewashed.