Cost of Fat Transfer from Breast to Butt?

This procedure is not routinely performed.  There is not enough fat to transfer from breast unless the breasts are massive.

Thank you for your question. The cost average varies depending the doctor and location. I would suggest to be treated by board certified plastic surgeon with experience in this procedure, to get the best desired results.
Respectfully,-Dr. Emmanuel Mallol Cotes.- 

A Brazilian Butt Lift starts at 6,500, and varies depending on the number of areas treated, treatment length, and complexity of the procedure.

I am not sure that you could obtain sufficient amounts of fat from the breasts to adequately augment the buttocks. Generally this may take a minimum of 300cc and upwards of 700cc to achieve sufficient buttock enlargement. This would require that at least twice as much be harvested (600 to 1400cc) to process and purify.
Fees would take into account the amount of time which is significant. This would range from 6-12,000. However, this is only an estimate.

Hello dear!
Thanks for the question.
The average cost varies a lot depending on the clinic, the country and the plastic surgeon. l recommend you to make an appointment with a board certified plastic surgeon to talk about your goals and anything you need to know.
Good luck :)

There are generally better donor sites than the breasts for fat transfer. Consult with three board certified plastic surgeons who are expert and experienced in fat transfer.Fat Transfer like other cosmetic surgery varies considerably across the
country and even in the same area. South Florida tends to have lower fees then
more expensive areas such as New York or Los Angeles. We charge starting at $4000 + MD
Anesthesia related costs for fat transfer to the buttocks. Since you can get quality work
at lower costs, patients will travel from throughout the state, the country,
and internationally to have surgery in South Florida.

To ensure that you are receiving quality work with personalized care at the
most cost effective prices, consult with board certified plastic surgeons that
own their own nationally accredited facilities. The quality must be maintained
at the highest level to maintain accreditation. The surgeons also have
incentive to hire and train quality staff (to ensure that surgery is efficient
and enjoyable), to ensure comfortable and private facilities (to encourage
referral), and to eliminate waste (to ensure that these facilities can compete
effectively).

Wow now this is a fascinating question, most would want this in just the opposite direction!! I would have to see photos of your two areas to determine if this was even feasible.  By removing fat from the breast you may create a droop to it, by not putting enough in the buttock you may not notice it. Be careful with this concept and seek someone who has done a lot of these.