BBL Shapes: The 4 Butt Types, BBL Styles and How to Choose Yours

In this guide17 sections

1. Key Points
2. What Are the 4 Butt Shapes?
3. How Do I Know My Butt Shape?
4. Which BBL Shape Suits My Body Type?
5. What Are the Different Types of BBL Styles?
6. Natural BBL vs Extreme BBL: What’s the Difference?
7. What Is the Best BBL Shape?
8. How Does the Waist-to-Hip Ratio Change Your BBL Shape?
9. BBL Sizes: How Big Can You Go With a BBL?
10. Can a BBL Fix Hip Dips?
11. How Do Your Frame and Donor Fat Limit Your BBL Shape?
12. How Do Surgeons Plan Your BBL Shape?
13. How Do I Tell My Surgeon What BBL Shape I Want?
14. Can a BBL Be Reshaped?
15. Frequently Asked Questions
16. Brazilian Butt Lift in London
17. References

The main BBL shapes are the round or “bubble” shape, the heart (upside-down heart) shape, the hourglass shape and a squarer, athletic shape, and the one that suits you depends on the butt shape you start with. Surgeons describe four natural buttock shapes (O, A, H and V), and a Brazilian butt lift can enhance or reshape each of them within the limits of your frame, your waist-to-hip ratio and your donor fat.

This guide covers the different types of BBL shapes, the BBL styles people ask for, natural vs extreme BBL, BBL sizes, hip dips, and how to explain the shape you want. Much of the shaping comes from liposuction rather than fat transfer, so it is worth reading alongside our guide to 360 liposuction, the most common partner procedure.

What Are the 4 Butt Shapes?

Surgeons often assess the buttocks using a frame classification published in 2006, which looks at the outline formed by the waist, hips and upper thighs, the gluteal muscle, how the muscle relates to the frame, and how much the buttock has dropped^[1]. Seen from behind, most people fit one of four butt types.

Round (O-Shaped) Buttocks

Round buttocks are full in both the upper and lower halves, with a curved outline at the hips. This is what most people mean by a “bubble butt”. A BBL for an O-shaped bum usually adds projection and lift rather than width, and slimming the waist makes the roundness more obvious.

Heart (A-Shaped) Buttocks

A-shaped, or upside-down heart, buttocks are narrower at the waist and fuller lower down, carrying volume at the base of the buttock and into the upper thighs. This shape often comes with a pear or hourglass figure. A BBL usually adds projection to the upper buttock and sharpens the waist, so the result looks lifted rather than heavier at the bottom.

Square (H-Shaped) Buttocks

Square, or H-shaped, buttocks have a fairly straight line from waist to thigh, often with fat at the flanks (“love handles”) and little inward curve, so the bum can look flat or boxy. This shape changes most with a BBL: liposuction creates a waist, and fat placed in the upper outer buttock and hip turns the straight line into a curve.

Inverted (V-Shaped) Buttocks

V-shaped buttocks are fuller at the top and narrower towards the thighs. What causes V-shaped buttocks is usually a mix of genetics, a narrower pelvis, fat stored around the middle and, after the menopause, a gradual shift of fat away from the lower buttock as oestrogen falls. A BBL for a V-shaped bum adds volume low and to the sides, and slims the waist and lower back.

Some guides add a fifth, flat or “I-shaped” bum with little projection or fat. It is common in slim people and athletes, and it raises a different question: whether there is enough donor fat for a BBL at all.

How Do I Know My Butt Shape?

Stand in front of a full-length mirror in fitted clothing and compare the narrowest point of your waist, the widest point of your hips and the line into your upper thigh. An outline that curves in and out suggests A or O, a fairly straight line suggests H, and fullness that sits high and tapers down suggests V.

At consultation your surgeon examines you standing, from the back, side and front, and assesses the bony pelvis, the gluteal muscle, the fat under the skin, any hollows at the sides of the hips, the crease under the buttock and skin quality. Research based on 1,320 photographs and measurements of 132 women concluded that buttock surgery is about more than projection and volume: the result must be in balanced proportion with the rest of the body^[2].

Which BBL Shape Suits My Body Type?

Your natural shape does not lock you into one result, but it shapes what is realistic:

• O-shaped (round): a round or bubble BBL with extra projection, or an hourglass if the waist is slimmed.
• A-shaped (heart): an enhanced heart shape or hourglass; the change is often subtler as the curve is already there.
• H-shaped (square): an hourglass or round BBL, with most of the change from waist liposuction and fat to the hips.
• V-shaped (inverted): a round or heart BBL, with fat placed low and to the sides.

Square shaping is mainly requested by men. A male BBL builds a squarer, projected shape in the upper and central buttock and leaves the hips untouched so the result stays masculine.

What Are the Different Types of BBL Styles?

When people search for BBL styles, they are usually describing an overall look rather than a buttock shape. These are the styles patients most often bring to consultation.

Natural BBL

A natural BBL adds moderate volume and lift that looks as though it could be your own shape, with a refined waist and smooth transitions into the lower back and thighs. It is a common request, often described as a subtle, tasteful or “natural def” BBL.

Athletic or Sporty BBL

An athletic BBL gives a firm, lifted, slightly squarer look with projection in the upper buttock, as though built in the gym. Waist liposuction is usually modest and the hips are not widened much. It suits slimmer people with an H or O frame.

Hourglass BBL (“Slim Thick”)

The hourglass BBL creates a small, snatched waist with fuller hips and buttocks tapering into the thighs. It depends heavily on liposuction of the flanks, back and abdomen and on fat placed at the sides of the hips. “Slim thick” describes the same idea: a slim upper body with a full lower body.

Round or Bubble Butt BBL

A bubble butt BBL, sometimes called the classic Brazilian shape, aims for an even, round buttock with projection in both halves. It usually needs more fat than other styles and can be planned for almost any natural shape if there is enough donor fat.

Heart-Shaped BBL

The heart-shaped BBL puts more volume in the lower buttock and hips, with a smaller waist above. It is close to the hourglass but with the fullness lower down, and suits A, H and V frames.

Extreme BBL

An extreme BBL aims for maximum volume and a very small waist, often modelled on edited social media images. It needs a large amount of donor fat, stretches the skin, and carries a higher risk of irregularities, asymmetry and fat loss. Our surgeons will not over-fill beyond what your tissues can safely hold.

Natural BBL vs Extreme BBL: What’s the Difference?

The difference is proportion. A natural looking BBL matches your height, hip width and thighs, keeps a smooth curve from the lower back into the buttock, and moves and feels like your own tissue. An extreme BBL prioritises size, so the buttock projects well beyond the frame. When people ask how to tell a BBL from a natural bum, they are usually spotting one of these:

• A “shelf”: a sharp step between the lower back and a very projected upper buttock.
• A pinched waist: heavy liposuction can make the waist look too small for the ribcage.
• Hips that stop abruptly: full hips above a thin thigh, with no smooth transition.
• Irregular texture: lumps or dents where too much fat was placed in one area.

To get a natural BBL, the plan treats the waist, hips, buttocks and thighs as one unit. In a 2016 survey of 1,146 people, the most attractive side profile had its fullest point at the middle of the buttock rather than high up^[3]. Fat also has to settle: the buttocks feel firm at first, then soften as the skin relaxes around the graft, which our guide to BBL fluffing explains week by week.

Real Centre for Surgery patient, BBL with liposuction to the waist and abdomen, front oblique view. Individual results vary.

What Is the Best BBL Shape?

The best BBL shape is the one that suits your frame. Research does show broad preferences: in a 2016 population analysis published in Plastic and Reconstructive Surgery ↗, 44.2% of respondents rated a waist-to-hip ratio of 0.65 as the most attractive from behind, with 0.60 next, and the preferred side profile had a ratio of 0.70 with projection at the midpoint of the buttock. Preferences did not differ significantly by age, gender or ethnicity^[3].

These numbers are a guide, not a target everyone can reach. Your waist-to-hip ratio depends on your ribcage and pelvis as well as fat, and a very small waist is not possible with wide ribs or little fat to remove. That is why two people asking for “the same” BBL are given different plans.

Real Centre for Surgery patient, photographed at least six months after BBL surgery.

You can see results across different body types in our BBL before and after photos.

How Does the Waist-to-Hip Ratio Change Your BBL Shape?

Much of the curve in a BBL comes from what is taken away. Removing fat from the flanks, lower back and abdomen narrows the waist and makes the hips and buttocks look fuller before any fat is transferred. Two areas matter most:

• The lower back. Fat here blurs the point where the back meets the buttock. Removing it creates the inward curve, sometimes called the “BBL arch”, that makes the buttock look projected.
• The flanks. Slimming the love handles narrows the waist from every angle and has the biggest effect on the ratio.

At Centre for Surgery, fat is harvested by power-assisted liposuction (PAL) or VASER, and your surgeon recommends the method that suits your tissues. A tummy tuck and BBL are never combined in the same operation here, as they need opposite positions on the operating table; when both are wanted, they are staged 3 to 6 months apart.

BBL Sizes: How Big Can You Go With a BBL?

There is no standard BBL size chart. BBL size is measured in the volume of fat transferred, and how big the result looks depends on your height, frame and starting shape as much as on millilitres. As a guide from our own procedures:

• Mini BBL: around 800 to 1,000 ml in total (400 to 500 ml per side) from two donor areas.
• Full BBL: around 1,600 to 2,000 ml in total from several donor areas.
• Skinny BBL: a modest, proportionate volume from four or five donor sites in slimmer patients.

A 2016 systematic review and meta-analysis of 4,105 patients ↗ found a mean of around 400 ml of processed fat injected into each buttock^[4], and in a survey of 853 Brazilian plastic surgeons the most common volume was 200 to 399 ml per buttock^[5]. Our guide to how much fat is transferred in a BBL goes into more detail.

Bigger is not always possible or safer. Fat needs a blood supply to survive, and the tissues can only hold so much before pressure rises, survival falls and irregularities appear. Around 30 to 50% of transferred fat is reabsorbed in the first few months, so surgeons over-fill slightly, and the result at 3 to 6 months is the one that lasts. In a prospective ultrasound study of 50 women who had fat placed only under the skin, the fat layer thickened by an average of 56.5% straight after surgery and thinned by about 18% over the next 12 months, keeping most of the gain^[6].

Can a BBL Fix Hip Dips?

Often, at least in part. Hip dips (violin hips) are the inward curves at the sides of the hips between the pelvis and the top of the thigh bone. They come mainly from your skeleton, with the skin tethered more tightly to deeper tissue at that point.

A BBL can soften hip dips by placing fat into the upper outer quadrant of each buttock and along the outer hip, giving a more continuous line from waist to thigh, and liposuction above and below the dip smooths it further. Fat cannot change the bone underneath, so a deep dip on a narrow pelvis may improve rather than disappear. Our article on hip dip surgery explains the options.

How Do Your Frame and Donor Fat Limit Your BBL Shape?

Two things set the ceiling on any BBL shape:

• Your frame. Pelvic width, hip height, torso length and ribcage size cannot be changed by fat transfer. A narrow pelvis can be given curves, but not the hip width of a wider frame.
• Your donor fat. A BMI of about 23 to 28 usually gives enough fat for a standard BBL, and your weight should be stable for at least 3 months (6 to 12 months after major weight loss).

If you are slim, a skinny BBL gathers smaller amounts of fat from several areas for a modest change, and a mini BBL suits a subtle lift. Where there is not enough fat for the volume you want, buttock implants can add projection, with fat transfer to soften the edges. If loose skin is the problem, a buttock lift may be needed instead of, or as well as, a BBL. After surgery, surviving fat grows and shrinks with your weight, so the shape lasts best at a stable weight.

How Do Surgeons Plan Your BBL Shape?

Planning starts with you standing. Your surgeon marks the areas for liposuction, the waistline to be created, the hollows to fill and the zones of the buttock that will receive fat. The shape comes from how much goes into each zone: more in the upper outer buttock and hip for an hourglass, more centrally for projection, more low for a heart shape.

Depth matters for safety as well as shape. Fat placed in or under the gluteal muscle can enter large veins and travel to the lungs. A 2017 ASERF task force report in Aesthetic Surgery Journal ↗, covering nearly 199,000 cases, found 32 deaths from fat embolism and a significantly higher rate where surgeons injected into the deep muscle^[7], and the Brazilian survey found the risk of death was 16 times greater with intramuscular injection^[5].

At Centre for Surgery, fat is placed only in the subcutaneous layer above the gluteal muscle, never into or beneath it, under real-time ultrasound guidance on every BBL, using a blunt cannula and expansion vibration lipofilling (EVL). Ultrasound helps with shaping too: a 2023 study of 4,150 ultrasound-guided BBLs in Aesthetic Surgery Journal ↗ showed surgeons could confirm the fat stayed under the skin and target specific compartments of the buttock to build projection and correct contour irregularities^[8]. Our guide to ultrasound-guided BBL explains the technique. The operation is a day case under TIVA (total intravenous anaesthesia) and takes 3 to 4 hours.

How Do I Tell My Surgeon What BBL Shape I Want?

Clear communication is the most practical thing you can do for your result. Before your consultation:

• Bring photos of bodies with a frame like yours, with similar height, hip width and build, not just a buttock you like.
• Include side and oblique views. Projection and the lower back curve are judged from the side.
• Bring photos of what you do not want. These are often more useful than goal photos.
• Be wary of edited images. Filters, posing and editing apps change proportions in ways surgery cannot match.
• Say what matters most: projection, hip width, a smaller waist or lift.

Your surgeon will tell you honestly which parts are achievable and may suggest a smaller first step. They will also ask how you feel about your body more generally: a 2024 meta-analysis of 65 studies and more than 17,000 patients found features of body dysmorphic disorder in around 18.6% of people seeking plastic surgery^[9], a condition in which surgery rarely brings satisfaction. We recommend a two-week cooling-off period before you decide, and further consultations before surgery are free.

Can a BBL Be Reshaped?

Yes. The final shape takes 3 to 6 months to appear, so judging it early can mislead. Once it has settled, a revision can add fat to areas that are uneven or have lost volume, and liposuction can reduce areas that are too full. A BBL cannot be fully reversed, as the surviving fat has its own blood supply, but it can be refined. At Centre for Surgery, revision is discussed at your 6-month review, and you can be seen sooner if you are worried. Our guide to revision BBL explains when it helps.

Frequently Asked Questions

Brazilian Butt Lift in London

BBL surgery at Centre for Surgery is performed by GMC-registered surgeons at our CQC-regulated Baker Street hospital, rated Good overall by the CQC. Every BBL is ultrasound-guided, with fat placed only in the layer above the gluteal muscle, and is carried out as a day case under TIVA. Your surgeon will assess your natural shape, frame and donor fat and plan a shape that suits your proportions, and the consultant who assesses you is the consultant who performs your surgery. Aftercare includes your surgeon’s direct number for the first 24 hours, contact with our nursing team over the first two weeks and follow-up reviews. We recommend a two-week cooling-off period before you go ahead. Your initial consultation is £100, redeemable against the cost of surgery if you go ahead. Finance isn’t available for BBL at Centre for Surgery, so the procedure is self-funded; our BBL cost guide explains what is included.

Phone: 020 7993 4849 | Address: 95–97 Baker Street, Marylebone, London W1U 6RN
Contact us to schedule a consultation

References

1. Mendieta CG. Classification system for gluteal evaluation. Clinics in Plastic Surgery 2006;33(3):333–346. doi:10.1016/j.cps.2006.04.006 ↗
2. Cuenca-Guerra R, Quezada J. What makes buttocks beautiful? A review and classification of the determinants of gluteal beauty and the surgical techniques to achieve them. Aesthetic Plastic Surgery 2004;28(5):340–347. doi:10.1007/s00266-004-3114-6 ↗
3. Wong WW, Motakef S, Lin Y, Gupta SC. Redefining the ideal buttocks: a population analysis. Plastic and Reconstructive Surgery 2016;137(6):1739–1747. doi:10.1097/PRS.0000000000002192 ↗
4. Condé-Green A, Kotamarti V, Nini KT, et al. Fat grafting for gluteal augmentation: a systematic review of the literature and meta-analysis. Plastic and Reconstructive Surgery 2016;138(3):437e–446e. doi:10.1097/PRS.0000000000002435 ↗
5. Cansancao AL, Condé-Green A, Gouvea Rosique R, Junqueira Rosique M, Cervantes A. “Brazilian butt lift” performed by board-certified Brazilian plastic surgeons: reports of an expert opinion survey. Plastic and Reconstructive Surgery 2019;144(3):601–609. doi:10.1097/PRS.0000000000006020 ↗
6. Cansancao AL, Condé-Green A, David JA, Vidigal RA. Subcutaneous-only gluteal fat grafting: a prospective study of the long-term results with ultrasound analysis. Plastic and Reconstructive Surgery 2019;143(2):447–451. doi:10.1097/PRS.0000000000005203 ↗
7. Mofid MM, Teitelbaum S, Suissa D, et al. Report on mortality from gluteal fat grafting: recommendations from the ASERF Task Force. Aesthetic Surgery Journal 2017;37(7):796–806. doi:10.1093/asj/sjx004 ↗
8. Pazmiño P, Del Vecchio D. Static injection, migration, and equalization (SIME): a new paradigm for safe ultrasound-guided Brazilian butt lift: safer, faster, better. Aesthetic Surgery Journal 2023;43(11):1295–1306. doi:10.1093/asj/sjad142 ↗
9. Kaleeny JD, Janis JE. Body dysmorphic disorder in aesthetic and reconstructive plastic surgery: a systematic review and meta-analysis. Healthcare (Basel) 2024;12(13). doi:10.3390/healthcare12131333 ↗

Related Articles

• Different Types of Brazilian Butt Lift
• How Much Fat is Transferred to the Buttocks in a BBL?
• Hip Dip Surgery — What It Is, How It Works and What to Expect
• Skinny BBL vs BBL: Which Suits a Slim Frame?