I'm looking into getting a BBL I'm 21, 5'3 and weigh 145 lbs. is that enough fat to get transferred.

It's a good question, but it really requires an in person exam. During the exam your surgeon will evaluate the amount of extra fat located on your abdomen, back, flanks, thighs and decide how much extra you have to donate to your buttocks. The amount of fat needed depends on the shape and size of your buttocks currently. You'll get the best answers by visiting a board-certified plastic surgeon in person. Good luck with your upcoming surgery.

Great question.  It is difficult to assess your body structure or amount of fat by just height and weight, the best recommendation is to have a consultation with a plastic surgeon so that a proper examination can be performed and recommendation provided.  With that said, what I usually tell patients is that I will try my best to remove as much fatty tissue as possible from all areas of the body so that I have enough tissue to transfer to the buttock.  This amount also depends on the degree of augmentation you desire.\If you do not have enough fatty tissue, another option is gluteal implants, or a combination of both.  Best of luck and hope this information help!- Dr. Roger Tsai