Small burns that just create a little blister usually heal on their own without any medical treatment.
But if you get a more severe burn then you should call 911 or seek medical attention right away or as soon as possible.
Really severe burns do require immediate medical attention because it can be fatal.
If the burn you have appears charred or has patches of white, brown or black or the burn is deep or the burn causes the skin to become leathery or dry then you need medical attention.
Always medical attention if you do get a very severe burn such as a burn to the face or other parts of the body that is more than just a little burn.