How Long Does Butt Filler Last?

Butt filler made from hyaluronic acid usually lasts between 12 and 18 months before your body breaks it down completely, and most people notice the volume softening gradually over the second half of that time. At Centre for Surgery, the non-surgical butt lift uses HYAcorp, a hyaluronic acid body filler, injected by surgeons in a sterile theatre under ultrasound guidance. A top-up at around 12 to 18 months keeps the shape going if you want to maintain it.

This guide explains why bum filler fades, what makes butt injections last longer or shorter, aftercare, how filler compares with fat transfer and collagen stimulators, and why permanent fillers and illegal “booty shots” are so dangerous. For more on the product itself, read our guide to HYAcorp fillers for buttocks, and for the safety debate around high-volume injections, see our article on the liquid BBL in the UK.

How Long Does Bum Filler Last?

For hyaluronic acid (HA) butt filler, the realistic answer is around 12 to 18 months. The filler gives an immediate change on the day, settles over a week or two, and then very slowly loses volume as your body absorbs it. Most people are aware of a softer, less projected shape somewhere after the first year.

The research supports that range. A 2023 systematic review of hyaluronic acid gluteal augmentation in Aesthetic Plastic Surgery ↗ pooled 10 studies covering 168 patients and estimated the duration of effect at 16.16 months on average^[1]. Most of the included studies showed a significant improvement in patient satisfaction.

A prospective study shows what that fading looks like in practice. In a 2025 prospective multicentre study of 30 women in the Journal of Cosmetic Dermatology ↗, satisfaction peaked at 90% one month after hyaluronic acid buttock filler and fell to 62% at 12 months, which the authors put down to normal breakdown of the gel^[2]. Ultrasound in the same study confirmed the filler sat in the fatty layer under the skin and was gradually absorbed, with no migration or lumps.

Ranges quoted online run from 6 months to 2 years, reflecting differences in product, volume and the person treated. Buttock injections described as lasting “forever” are not hyaluronic acid, and we explain below why that should be a warning sign.

How Do Bum Fillers Work, and Why Do They Wear Off?

Hyaluronic acid is a sugar molecule found naturally in skin and connective tissue. In a filler, the hyaluronic acid is cross-linked into a gel so it holds its shape and resists breakdown. Body fillers such as HYAcorp are made for large-volume contouring, with a thicker consistency and larger particles than the fillers used in the face.

That firmness matters in the buttocks. A 2026 laboratory comparison of hyaluronic acid body fillers ↗ found that HYAcorp’s body fillers were among the stiffest and most elastic tested, properties the authors linked to better performance under the heavy, repeated loading of sitting and movement^[3].

No hyaluronic acid filler lasts forever. Your body has its own enzymes (hyaluronidases) and normal tissue processes that slowly break the gel down into small fragments, which are cleared like naturally occurring hyaluronic acid. The cross-linking slows this process down but does not stop it. So the question is not whether butt filler wears off, but how quickly it does so in your body.

What Makes Butt Injections Last Longer or Shorter?

Four factors have the biggest influence on how long butt injections last: metabolism, activity, pressure and volume. Your weight and the product used also play a part.

• Metabolism. People break hyaluronic acid down at different rates, so two people given the same volume can see it fade months apart. Those with a naturally fast metabolism often notice the filler softening sooner. This is largely individual and is hard to change.
• Activity. Very active people, especially those doing intense or high-volume training, tend to absorb filler faster. Increased blood flow and movement in the treated area are thought to speed up breakdown. This is not a reason to stop exercising; it simply means athletes may need top-ups sooner.
• Pressure. The buttocks carry your weight every time you sit. Constant, heavy pressure on the treated area, for example long days at a desk or regular cycling and spinning, adds mechanical stress to the gel. Pressure in the first 24 to 48 hours matters most, while the filler is settling.
• Volume. A larger amount of filler generally takes longer to absorb than a small one, and the change remains visible for longer. A small volume used to soften a hip dip may look subtle sooner than a fuller treatment of the upper buttock.
• Weight changes. Filler sits in the fat layer under the skin. If you lose a lot of weight, the surrounding fat shrinks and the overall shape can look flatter even though filler remains. Gaining weight changes the shape in the opposite direction.
• Product and placement. A firm body filler placed precisely in the fatty layer, under ultrasound, behaves more predictably than a thin facial filler or one placed blindly.

There is little direct evidence that smoking changes how long buttock filler lasts, but stopping helps healing after any injection.

How Long Does Bum Filler Take to Settle?

The change in shape is visible immediately, but it takes a short while to see the true result. A typical timeline at Centre for Surgery looks like this:

• Day of treatment: the session takes about 45 to 60 minutes under local anaesthetic and numbing cream. You walk out the same day and can return to normal daily activity.
• First 24 to 48 hours: avoid direct pressure on the buttocks and strenuous exercise while the filler settles.
• Days 2 to 5: mild swelling, soreness and bruising usually settle.
• Weeks 1 to 2: the settled result is clear once swelling has gone.
• Weeks 2 to 4: your follow-up review with your surgeon checks the shape and symmetry.
• Months 12 to 18: the filler has gradually softened, and a maintenance session can be planned if you want to keep the result.

That pattern matches the published data. In a 2025 multicentre study of HYAcorp MLF2 for buttock augmentation ↗, side effects were generally mild to moderate and usually resolved within 2 to 7 days, the most common being swelling, pain and redness^[4].

Bum Filler Aftercare: How to Make Your Results Last

Aftercare after butt filler is simple compared with surgery. No compression garment is needed and most people go back to work the same or the next day. The steps that help the filler settle well and last are:

• Avoid direct pressure for 24 to 48 hours. Sit on the backs of your thighs or lean to one side where you can, and sleep on your front or side for the first night or two.
• Pause strenuous exercise for 24 to 48 hours. Walking is fine from the start. Squats, lunges, heavy leg work, running and cycling can usually resume after 24 to 48 hours.
• Do not massage the area unless your surgeon asks you to, as this can move filler before it settles.
• Keep the injection points clean and avoid hot tubs, saunas and swimming pools until they have closed, to reduce the risk of infection.
• Keep your weight stable over the following months.
• Attend your review at 2 to 4 weeks so your surgeon can check symmetry and discuss whether a second session is worthwhile.

Call the clinic straight away if you notice increasing pain, a red, hot or swollen area, fever, skin colour changes or a hard lump after the first few days. Call 999 if you have sudden breathlessness, chest pain or cough up blood.

How Much Bum Filler Do You Need?

How much filler you need depends on your starting shape, your goal and how much change your tissues can hold. At Centre for Surgery the number of vials is agreed at consultation, and treatment is usually built up over 1 to 3 sessions spaced around four to six weeks apart, rather than injecting a large volume at once.

Published studies give a sense of scale. The average injected volume was about 85 ml in the HYAcorp multicentre study^[4] and about 44 ml in the one-year prospective study^[2], while the systematic review reported a mean of around 207 ml across its studies^[1]. That is why “100ml bum filler before and after” photos online usually show a subtle lift rather than a dramatic change.

The honest message is that even a generous course of filler gives a modest change. If you are looking at photos of a much larger, rounder buttock, you are almost always looking at fat transfer or implants, not filler. People who want to correct a single hollow, such as a hip dip, often need less product than a full buttock treatment. Our guide to hip dip surgery explains when filler or fat transfer suits that area better.

Is Butt Filler Reversible?

Yes. Hyaluronic acid filler can be dissolved with hyaluronidase, an enzyme injected into the treated area that breaks the gel down within days. This is one of the main reasons we use hyaluronic acid rather than a permanent product. If filler lands in the wrong place, forms a lump, becomes infected or simply does not look right to you, there is a way back.

Reversibility is also a safety backstop. If filler is accidentally injected into a blood vessel, the most serious risk with any injectable, hyaluronidase is part of the emergency treatment. Ultrasound guidance helps your surgeon see the tissue layers and vessels during injection, which is why every non-surgical butt lift at Centre for Surgery is performed under ultrasound.

Butt Filler vs BBL: Which Lasts Longer?

A Brazilian butt lift lasts far longer. In a BBL, your surgeon removes fat by liposuction from areas such as the tummy, flanks and back, then injects it into the fatty layer of the buttocks, above the muscle and under real-time ultrasound guidance. Around 50 to 70% of the transferred fat survives. The fat that survives has its own blood supply and is permanent from about six months, changing in size with your weight like any other fat. Our guide on how long BBL results last explains this in detail.

Here is how the two compare on the points that matter most:

• How long it lasts: butt filler around 12 to 18 months; fat transfer permanent once established, with the final result at 3 to 6 months.
• How much change: filler gives a modest, subtle change; a BBL can give significant volume and also slims the donor areas, which sharpens the waist.
• The procedure: filler takes 45 to 60 minutes under local anaesthetic; a BBL is a day case under TIVA (total intravenous anaesthesia) taking 3 to 4 hours.
• Recovery: filler has no real downtime; after a BBL you avoid sitting directly on your buttocks for 2 weeks, wear a compression garment for 6 weeks and take 1 to 2 weeks off work.
• Reversibility: filler can be dissolved; a BBL cannot be fully reversed, although it can be revised.
• Cost over time: filler is cheaper per session but repeats every year or so; a BBL is a single, larger cost. Our guide to BBL cost in London explains what is included.

Filler makes sense if you want a subtle change, are not ready for surgery, are too slim for enough donor fat, or want to see how more volume feels before committing. A BBL makes sense if you want a lasting, more noticeable change and are happy with a surgical recovery. In between, a mini BBL uses less fat from two donor areas with a shorter recovery, and a skinny BBL is designed for people with a lower BMI. If your concern is loose, sagging skin rather than volume, neither filler nor fat will lift it, and a buttock lift may be the right operation. For a fuller side-by-side, read butt injections vs BBL.

How Does Butt Filler Compare With Poly-L-Lactic Acid Injections?

Poly-L-lactic acid (PLLA) is a collagen stimulator rather than a filler. Instead of adding gel, it triggers your body to lay down new collagen over several weeks, so the result builds gradually and needs a course of treatments. Clinics usually quote results lasting around two years, which is longer than hyaluronic acid.

The trade-offs are real. In a retrospective review of 60 patients treated with PLLA to the buttocks, a visible volume change needed at least 20 vials across 1 to 3 sessions^[5]. PLLA cannot be dissolved if you dislike the result or develop nodules, and the change appears slowly rather than on the day. Centre for Surgery does not use PLLA in the buttocks; we use hyaluronic acid filler so that the result is visible immediately and can be reversed.

Why Are Permanent Butt Fillers Dangerous?

Permanent and semi-permanent fillers, including PMMA (polymethyl methacrylate), liquid silicone and polyacrylamide hydrogel, are sometimes sold as a way to avoid repeat treatments. They are not used at Centre for Surgery, and the evidence on their complications in the buttocks is concerning.

• PMMA: in a 2025 Brazilian case series of 12 women who had high-volume PMMA injected into the buttocks, all developed high calcium levels in the blood or urine, 83% developed kidney dysfunction and half developed kidney stones, appearing anywhere from 40 days to 8 years after injection^[6]. Kidney function stayed abnormal in most patients.
• Silicone and other non-absorbable fillers: a 2025 systematic review of kidney complications after filler injections found the buttocks were the injected site in 72% of cases, with silicone, methacrylate and oil the products involved; 3 of the 29 patients died^[7].
• Polyacrylamide hydrogel: a 2025 report described three women with long-term major complications after polyacrylamide hydrogel injections to the breasts and buttocks, needing surgical removal and reconstruction; the authors noted that the long-term toxicity of polyacrylamide remains uncertain^[8].

The common thread is that permanent fillers cannot be dissolved. If they migrate, harden, become infected or trigger inflammation, removing them means surgery, often with scarring and contour deformity, and complete removal is not always possible. Problems can also appear many years after the injection. Hyaluronic acid has to be repeated, but that temporary nature is part of what makes it safer.

Are Illegal Butt Injections (“Booty Shots”) Safe?

No. “Ass shots”, “booty shots” and cheap “BBL injections” offered in homes, hotels, salons or at parties often involve industrial liquid silicone, oils or unidentified products injected in large volumes by people who are not doctors. The results can be catastrophic.

A 2024 scoping review of illicit cosmetic injections in Acta Cirúrgica Brasileira ↗ identified 142 publications from 28 countries and found the buttocks were the most commonly injected area (35%)^[9]. The most frequently reported complications were granulomas (inflammatory lumps), skin damage, infection and lung complications. Silicone can travel to the lungs and cause silicone embolism syndrome, which can be fatal within hours or days of injection.

Even legitimate hyaluronic acid carries serious risk when it is injected badly. The 2023 systematic review noted that, although complications were uncommon, buttock filler has been linked to bleeding in the lungs and death^[1]. That is why the setting, the injector and the imaging matter as much as the product.

The UK government is moving to tighten the rules. On 21 October 2026, the Department of Health and Social Care announced a consultation on draft proposals under which fillers injected anywhere other than the face, including liquid BBLs, would be legally defined as cosmetic surgical procedures that only doctors could perform^[10]. These are proposals rather than law at the time of writing. Warning signs that a provider is unsafe include:

• the injector is not a doctor or will not give you their GMC registration number;
• treatment takes place in a home, hotel, salon or at a party rather than a CQC-registered clinic;
• the product is unlabelled, or described as “permanent”, “silicone” or “biopolymer”;
• no ultrasound or medical assessment is offered;
• the price is far below what regulated clinics charge.

If you have had injections from an unregulated provider and develop breathlessness, chest pain, confusion or coughing up blood, call 999 and tell the team what was injected. Our article on BBL risks explains how surgical safety rules for fat transfer have changed in recent years.

Who Is Butt Filler Not Suitable For?

The treatment is not suitable during pregnancy or breastfeeding, with an active infection in or near the area, or with a known allergy to hyaluronic acid. Tell your surgeon if you take blood thinners. If you have previously had any other substance injected into your buttocks, bring whatever details you have, as previous fillers change both the risks and the plan.

Frequently Asked Questions

Non-Surgical Butt Lift in London

The non-surgical butt lift at Centre for Surgery is carried out by GMC-registered surgeons at our CQC-regulated Baker Street hospital, rated Good overall by the CQC. We use HYAcorp hyaluronic acid body filler only, injected in a sterile theatre under ultrasound guidance, and every treatment includes a follow-up review at 2 to 4 weeks. Results are modest and last around 12 to 18 months, with a maintenance session recommended at that point if you want to keep the shape. Your surgeon will also talk you through surgical options such as a BBL, mini BBL or buttock implants if they would suit your goals better.

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

References

1. Mortada H, Alkadi D, Saqr H, et al. Effectiveness and role of using hyaluronic acid injections for gluteal augmentation: a comprehensive systematic review of techniques and outcomes. Aesthetic Plastic Surgery 2023;47(6):2719–2733. doi:10.1007/s00266-023-03458-0 ↗
2. Bussade M, Faria G, Barros M, et al. Assessment of hyaluronic acid filler in gluteal augmentation and contouring: a 1-year prospective study. Journal of Cosmetic Dermatology 2025;24(12):e70600. doi:10.1111/jocd.70600 ↗
3. Fontenete S, Alfertshofer M. Rheological and physicochemical properties of hyaluronic acid fillers for body contouring: clinical implications and anatomical considerations. Journal of Cosmetic Dermatology 2026;25(2):e70553. doi:10.1111/jocd.70553 ↗
4. Crabai P, Campos-Martínez L, Marchetti F, et al. Evaluating the safety and satisfaction of HYAcorp MLF2 for noninvasive buttock augmentation: a multicenter study. Plastic and Reconstructive Surgery Global Open 2025;13(1):e6415. doi:10.1097/GOX.0000000000006415 ↗
5. Durairaj KK, Devgan L, Lee A, et al. Poly-L-lactic acid for gluteal augmentation found to be safe and effective in retrospective clinical review of 60 patients. Dermatologic Surgery 2020;46(Suppl 1):S46–S53. doi:10.1097/DSS.0000000000002598 ↗
6. Ianhez M, Rodrigues LQ, Ianhez LE, et al. Hypercalcemia and renal complications following high-volume polymethyl methacrylate (PMMA) injections: a case series. Aesthetic Plastic Surgery 2025;49(23):6810–6815. doi:10.1007/s00266-025-05081-7 ↗
7. Posso AN, Cojuc-Konigsberg G, Mustoe A, et al. Renal complications associated with silicone, methacrylate, and oil-based fillers: a systematic review. Aesthetic Plastic Surgery 2025;50(5):2083–2091. doi:10.1007/s00266-025-05107-0 ↗
8. Cestepe F, Guclu B, Yildiran L, et al. Management of AQUAfilling filler application complications. Sisli Etfal Hastanesi Tip Bulteni 2025;59(2):251–254. doi:10.14744/SEMB.2024.04864 ↗
9. Gerk A, Telles L, Carroll M, et al. Use of industrial liquid silicone: a scoping review. Acta Cirúrgica Brasileira 2024;39:e395624. doi:10.1590/acb395624 ↗
10. Department of Health and Social Care. Cosmetic cowboys crackdown continues with new restrictions. GOV.UK, 21 October 2026. gov.uk ↗

Related Articles

• HYAcorp Fillers for Buttocks
• Liquid BBL in the UK: What It Is, How Long It Lasts and Is It Safe?
• Butt Injections vs BBL: Filler, Booty Shots and Surgery Compared
• How Long Do BBL Results Last?