Both treatments are used for the same concern: skin on the face or neck that has started to loosen. That makes them easy to mistake for two versions of one thing. They differ in the energy they use and in how deep that energy goes. This article sets them side by side, with the research behind each one and the questions worth asking before you choose. Radiofrequency microneedling, which you may also see suggested, is a different treatment, and it comes up under the other options near the end.
What radiofrequency and HIFU each do to the skin, and which layers they reach
Radiofrequency uses an electric current rather than a light source, as a 2012 review of radiofrequency in cosmetic dermatology puts it. A 2024 study of the two used together describes the monopolar kind raising the temperature of the dermis, the skin's middle layer. The heat makes collagen fibres partly unravel, contract and thicken. The same study describes radiofrequency prompting new collagen and elastin to form.
High-intensity focused ultrasound works differently. A 2025 review of how it works describes the energy reaching several skin layers and the superficial musculoaponeurotic system (SMAS), a layer that lies deeper than the skin. In those layers it creates small points of heat damage. Those points recruit fibroblasts, the cells that make collagen, and stimulate new collagen and elastin. All eleven authors of that review declared ties to the maker of one focused ultrasound device. Read it as an account of how the treatment is thought to work.
Both, then, work through heat. They differ in where that heat lands.
The clinic's pages on radiofrequency skin tightening and HIFU treatment set out how each is carried out here.
The same 2024 study put the usual split in a single sentence: radiofrequency works on the upper reticular dermis, while HIFU can reach the deeper reticular dermis and the SMAS layer. That study used monopolar radiofrequency, so its sentence may not describe every radiofrequency device.
The reticular dermis is the deeper part of the dermis. Focused ultrasound also acts in the dermis, so the two overlap there.
On the HIFU device at Nexus, each cartridge works at a set depth. On the face, 1.5 and 2.0 millimetres reach the dermis, 3.0 the deep dermis and 4.5 the SMAS. For the body, the deeper cartridges, at 6.0, 9.0 or 13.0 millimetres, reach the subcutaneous layer and are used on areas such as the tummy and thighs; when loose skin is the only concern on the body, the shallow 2.0 millimetre cartridge is used instead.
Is HIFU better than radiofrequency? As a general statement, neither ranks above the other. They work at different depths, so the useful question is which layer needs treating.
What a doctor checks before choosing between radiofrequency and focused ultrasound
Choosing starts with an examination. A doctor looks at where the looseness sits, how much laxity there is and the person's build. At Nexus, the first appointment is a consultation, with no treatment that day, and skin condition and recent treatments are reviewed before a radiofrequency course starts.
How much laxity there is matters. A 2023 systematic review of 16 studies of microfocused ultrasound found that positive results declined as laxity and body mass index (BMI) rose. It listed excessive skin laxity and a BMI above 30 as relative contraindications, which are reasons for caution rather than firm bars.
Body weight showed up in a 2014 trial that evaluated 93 people treated with microfocused ultrasound. No change was detected in 54.5% of those with a BMI above 30, against 12.2% of the rest.
Where looseness sits in more than one layer, the clinic's non-surgical face lift page explains how the layers are assessed together.
What the randomised trial comparing radiofrequency with HIFU found
The one randomised split-face trial we found that put the two against each other was published in 2019. Its 20 people had mild to moderate laxity. Each person had monopolar radiofrequency on one side of the face and microfocused ultrasound on the other, at the same visit. Microfocused ultrasound is a related form of focused ultrasound. Both sides improved on the trial's laxity scale, and the trial found no statistically significant difference between them. It also found no statistical differences in patient satisfaction or side effects.
Before this trial, its authors noted, no comparative clinical trials had been performed. One trial of 20 people cannot settle the choice for everyone, and no study we found ranks one treatment above the other. A non-surgical treatment gives a partial effect and is not equivalent to surgery, whichever energy it uses.
How the published improvement rates for HIFU depend on who rates them
Many of the studies of focused ultrasound tested microfocused ultrasound, and the figures here are given as each study reports them. Published improvement rates run from 58% to 92%, depending on the study, who rates the result and how. In the 2014 trial, blinded reviewers comparing photographs saw improvement in skin laxity in 58.1% of patients.
A 2025 meta-analysis of 42 studies found that investigators rated 89% of 411 patients as improved (95% confidence interval 81% to 94%). In the same analysis, 84% of 312 patients reported improvement themselves. That analysis was funded by the maker of one focused ultrasound device, and seven of its 12 authors declared ties to that maker. The 2023 review pooled investigator scores for 337 patients at 92%, while the improvements patients reported were mild.
Satisfaction varies in the same way, and it is a separate measure from improvement. In the 2025 analysis, 84% of patients reported some level of satisfaction, but 62% did when 'neutral' was one of the possible answers. The authors warn that counting neutral answers as positive may overestimate how well the treatment works. The clinic's guide to HIFU as a non-surgical facelift looks at two of these studies alongside other routes.
For radiofrequency, we found no pooled improvement rate. A 2022 systematic review of 121 articles reported improvement in skin laxity, elasticity and overall appearance, with satisfaction higher among people who wanted a modest change. It also reported tissue changes consistent with repair and with new collagen and elastin forming. A 2022 review of 23 studies found measurable improvement in skin laxity of the face and body.
The 2012 review was more cautious. It noted that many radiofrequency studies were not randomised, did not compare treatments and relied on subjective evaluation, and it described the results as modest.
What a session of radiofrequency or HIFU feels like, and its side effects
Pain scores for focused ultrasound are moderate. The 2025 meta-analysis combined the scores of 785 patients into a mean of 4.85 out of 10. The 2014 trial recorded average scores of 5.68 for the cheek, 6.09 under the chin and 6.53 below the jawline. Numbing cream is part of a HIFU session at the clinic.
For radiofrequency, the 2012 review described non-ablative treatment as tolerable. We found no pooled pain score for radiofrequency alone, and none of the study summaries we read reported a direct comparison of pain between the two.
When the two were used together in the 2024 study of 56 patients, all 56 had mild redness that passed, and no serious adverse events were reported. Pain scores were kept for 10 of the 56, and 8 of those 10 rated their pain at 5 out of 10.
Who usually suits radiofrequency or HIFU, and who should pause first
The studies say more about who suits focused ultrasound than about who suits radiofrequency. The 2023 review found that focused ultrasound tightened mildly to moderately lax facial skin. Every study it included was in women, and its authors call for studies in men.
For radiofrequency, the randomised trial enrolled people with mild to moderate laxity. The 2022 review of 121 articles found satisfaction higher among people who wanted a modest change. The 2012 review put the limit plainly: radiofrequency should serve as an alternative to surgery, not as an equivalent substitute.
At Nexus, radiofrequency is offered for loosening of the mid-face, in people from their late 20s to their 50s, and it works above the SMAS, the layer HIFU reaches.
Signals that a non-surgical treatment may suit
- Mild to moderate laxity, the range the studies describe
- A wish for a modest change, not a surgical one
- Readiness for a partial effect, checked at a review visit
Points to raise with the doctor first
- Heavier laxity, listed as a relative contraindication for focused ultrasound
- A BMI above 30, linked with less change after focused ultrasound
- Your medical history, medicines and skin condition
- What you hope to change, and what you would accept if the change is partial
These are signals from the studies, not rules. The doctor confirms whether either treatment suits you at the examination.
Nexus also names who should pause before HIFU: anyone who is pregnant or breastfeeding, anyone with a pacemaker or another implanted electronic device in the area, anyone with an infection, inflamed acne or an open wound there, and anyone who has had a toxin or filler injection there in the past two weeks. Before radiofrequency, inflamed skin is settled first, and metal implants near the area are talked through with the doctor before booking.
How radiofrequency and HIFU are combined, and what the order study found
The two can be combined, and two of the studies in this article did so. The 2024 study looked back at the records of 56 patients in Malaysia who had both. Its authors list its limits, among them a small sample, no randomised comparison of the two treatments, and photographs taken right after treatment rather than at a later follow-up.
A 2025 split-face study of 24 adults in Korea tested the order: radiofrequency then HIFU on one side of the face, and HIFU then radiofrequency on the other. Both orders led to clinical improvement with minimal side effects. On three-dimensional camera analysis, radiofrequency first gave slightly more wrinkle reduction, and tissue samples showed no marked difference between the orders.
At Nexus, when both the dermis and the SMAS need work, the two can be given weeks apart, or in one session if the examination supports it. The order, and whether to combine them at all, is decided at the consultation, after the doctor has examined you.
How long the effect of radiofrequency or focused ultrasound is reported to last
For focused ultrasound, the 2023 review found that the improvement continued up to one year, and it notes that longer-term follow-up data are not available. For radiofrequency, we found no pooled figure for how long the effect lasts.
How often a treatment is repeated is set by the doctor for the person. A review visit is part of the plan, and the doctor decides there whether anything more is needed.
What else exists for loose skin besides these two treatments
Radiofrequency and HIFU are two options among several, and a balanced choice weighs the others too, including no treatment at all.
Radiofrequency microneedling has its own page. For the wider picture, including creams and care at home, see our article on how to tighten loose skin.
Questions to ask the doctor before you choose either treatment
A good consultation should leave you clear on what is being treated, why, and what it will not change. These questions help you get there.
Common questions about radiofrequency and HIFU
In short, radiofrequency and HIFU both work through heat and reach different depths. The one randomised trial we found showed no statistically significant difference between them. The choice is made at a consultation, after the doctor has examined you.
