Running your washing machine during off-peak hours, like mid-morning or early afternoon, reduces energy costs and grid demand. Turns out, there might be a more ideal time of day to use your washing machine. “Heavily soiled clothes, for example, are best suited for a longer wash cycle instead of quick wash,” says Dennis Godynuk, owner of Comfort Appliance Repair TN. Noise ConcernsFor those living in a duplex, townhouse, or apartment, it's not appropriate to run a washing machine at night, regardless of peak hours. Follow Us On GoogleHowever, from a noise perspective, running a washing machine at night may not be practical for many, as this is when folks are trying to sleep.