I use either one. sometimes mix them. peanut oil is cheaper than it used to be. it used to be about $35 now it's $23 for 3 gals and $14 for 3 gals of veg. oil. since it doesn't get overheated with the electric fryer, the oil last a long time. it's still pretty clear after several turkeys. I drain the oil and clean the residue from the bottom and the basket after 4-6 birds and reuse if it doesn't smell burnt. it's surprising how little oil you use. I never have to add any after several turkeys. I'm fixing to crank the fryer back up to fry some oysters and fries before I clean it until next year. mmmmmmmmm