The cost of U tubes varies depending on what type you are looking for and where you are buying them from. It is therefore important that you know what kind of U tube that you want, before you can determine how much they will cost. For example, if you need a smaller quantity, they may be cheaper than ordering in bulk. On average, prices range from $3 to $12 dollars per foot depending on supply and demand. Additionally, larger companies will often give greater discounts than smaller ones.