I'm weird and just can't leave the oil in it, so I drain it and clean it up. Will add that a toilet brush (dedicated to fryer use only, lol) works great for cleaning under the burner tube. My only complaint is the groove around the inside of the thermometer, as the breading tends to accumulate there and is a little tricky to get out, but otherwise very easy to clean. I get a bit goofy over cleaning cooking stuff up, so most probably don't even notice, just had to figure out where that old breading was coming from when I dumped the oil back in it.