I wouldn't leave it for more than 4 hours or so at a time, so he can go potty. Otherwise he can be left longer if he uses wee pads and has plenty of food and water left out for him. My Chihuahua had separation anxiety and if I was gone for any time he would drag toilet paper all over the house and shred it in little pieces! I had to leave the t.v. On for him so he had company:)
Some Chihuahua can be left home longer. It depends on there size and age. The very small ones can only be left for short periods of times because of health issues. So they need a sitter and are quite a commitment for someone if they own one. The average size adults can hold there bladder longer and can be left for longer periods even up to 8 hours. I have a 4.5 lb Pomeranian and she can go 6-8 hours but she has a companion her older sister Jasmine who keeps her company. I also have puppy pads for when they can not hold it any longer.
Well,me myself hav a cute lil chihuahua and we've left her alone for 1-2 days and they were fine of course we had a friendly neighbour let them outside because my puppy is a rottie and can't hold it any longa!! Lol but they can be fine for up to 1,2,3 days.