THE SKIN EDIT · TREATMENT FOCUS
Acne Scarring: The Four Types and Which Treatments Suit Each
The spots have finally settled, but your skin has kept a few reminders. Some are flat brown or red marks. Others are little pits, broader dips or raised bumps. They often get grouped together as “acne scarring”, but they do not all need the same treatment.
The four main patterns are ice pick, boxcar, rolling and raised scars. The names are not especially elegant, but the differentiation can help explain why a treatment that works well for one person may do very little for another.
You can also have several types at once. Skin rarely organises itself neatly for our convenience.
Before booking a course of anything, the first question is whether you are looking at a scar, a mark or a mixture of both. Otherwise, you can spend quite a lot treating the wrong problem.
What are the different types of acne scarring?
The four main patterns are ice pick, boxcar, rolling and raised scars. Acne scars change the skin’s contour. Some sit below the surface because tissue has been lost or pulled down during healing. Others rise above it because the skin has produced excess scar tissue.
What are ice pick scars?
These look like tiny, deep punctures in the skin. The opening can be small, but the scar underneath is deeper than you might expect.
That is why a deep ice pick scar may barely change after a treatment aimed mainly at the surface. A small opening does not necessarily mean a small treatment challenge.
What are boxcar scars?
Boxcar scars are round or oval depressions with more clearly defined edges, rather like little craters.
They can be shallow or deep. That distinction matters: a shallow boxcar scar and a deep one may share a name without sharing the same treatment plan.
What are rolling scars?
Rolling scars are broader dips with gently sloping edges. Together, they can give the skin a rippled or uneven appearance, particularly when light comes from the side.
Some are tethered: fibrous bands beneath the skin pull the surface down. If that tethering is the main problem, treating only the surface may leave the cause untouched.
What are raised scars, and what is the difference between a hypertrophic scar and a keloid?
Raised scars sit above the surrounding skin. They include hypertrophic scars, which remain within the original affected area, and keloids, which extend beyond it.
They can develop along the jawline or on the chest, shoulders and back. They need a different approach from depressed scars because the problem is excess scar tissue rather than a depression that needs lifting.
Depressed scars are more common overall, and ice pick scars are often described as the most common individual type. There is no single “hardest” scar to treat: deep pits can be stubborn, while keloids can recur even after an initially good response.
Is it an acne scar, or is it a mark?
The simplest starting point is this: has the colour changed, the contour changed, or both? A flat brown or red patch is usually a mark. A pit, dip or raised patch suggests a structural scar.
A flat brown or grey-brown patch may be post-inflammatory hyperpigmentation (PIH). This is pigment left behind after inflammation.
A flat pink, red or purplish mark may be post-inflammatory erythema (PIE): a lingering colour change associated with the small blood vessels in the area.
A pit, dip or raised patch suggests a structural scar. You can also have colour sitting over a scar, which makes the distinction less obvious.
Flat marks often fade gradually over months, although some last much longer. Deeper pigmentation and marks in skin prone to pigment changes can be particularly persistent. There is no magic date at which a mark officially becomes permanent.
This matters because fading pigment and lifting a depression are different jobs. A serum may help the colour without changing the contour. A procedure intended for structural scars may be unnecessary if the main concern is a flat mark.
Before spending money on “scar removal”, make sure a scar is what you are treating.
Which acne scar treatment suits which scar type?
Treatment should follow the scar’s shape, depth and behaviour. Choosing the machine first and finding a reason to use it afterwards is the wrong way round.
Ice pick scars: targeted treatment for a deep problem
Selected ice pick scars may respond to TCA CROSS, where a clinician applies a concentrated acid precisely to the scar to encourage remodelling.
Some deeper scars may be better suited to punch excision, a small surgical procedure that removes the scar and closes the area.
Neither approach guarantees that the scar will disappear completely. The aim is to make a deep pit less noticeable.
TCA CROSS is also very different from applying an exfoliating acid at home. Concentrated acid can cause burns, pigment changes and further scarring if used incorrectly. This is firmly a clinician’s job.
Boxcar scars: depth decides the approach
Shallower boxcar scars may improve with treatments such as microneedling or fractional laser resurfacing, depending on the skin and the scar pattern.
Deeper, sharply edged scars may need a focal procedure such as punch elevation or excision, sometimes followed by resurfacing.
This is one reason a standard course of the same treatment does not suit every person with acne scarring. The label “boxcar” is a starting point, not the whole assessment.
Rolling scars: check what is pulling the skin down
Where rolling scars are tethered, subcision may be considered. This involves releasing selected fibrous bands beneath the skin.
In suitable cases, it may be combined with filler or followed by treatment for the remaining surface irregularity.
If a depression is being held down from underneath, repeatedly treating the top can be an expensive way to overlook the problem.
Subcision still has risks, including bruising, bleeding, infection, pigment changes and injury to nearby structures. Filler has its own risks, including rare but serious vascular complications.
Raised scars: a different treatment plan
Hypertrophic scars and keloids may be treated with scar-directed injections, selected laser treatments or silicone products, depending on the scar.
Keloids deserve particular care because they can grow beyond the original area and recur after treatment. Simply cutting one out without a plan to reduce recurrence can create another problem.
These scars should not automatically be given the same collagen-stimulating treatment used for depressed scars.
What if you have more than one type of acne scar?
You may need more than one approach, sometimes in stages. For example, a plan might address tethering first, then reassess the surface, with a separate focal treatment for a deep pit.
That does not mean everyone needs a long list of procedures. It means each treatment should have a clear job.
And sometimes the right answer is to leave a subtle scar alone. A small possible improvement may not justify the cost, downtime or risk. Treatment is optional, and doing less can be a perfectly reasonable decision.
Can acne scarring be removed completely?
Usually, the realistic goal is to make scars less noticeable rather than return the skin to a completely unscarred state. That may sound less exciting than “scar removal”, but it is a much more useful starting point.
Even surgically removing an individual scar replaces it with another scar, ideally one that is less conspicuous. Resurfacing can soften edges and improve unevenness, but it cannot promise perfectly smooth skin in every light.
There is also no honest percentage improvement that applies to everyone. Scar depth, tethering, skin characteristics, treatment choice and healing all affect the result. A percentage from a study is not a personal forecast.
A better discussion is specific:
- Can this depression become shallower?
- Can these edges look softer?
- Can the tethering be released?
- Can this raised scar become flatter or more comfortable?
- Is the likely improvement worth the recovery and risk?
Skin tone matters too. Darker skin can be treated, but the risk of post-inflammatory pigmentation needs careful consideration. Treatment choice, settings and aftercare should reflect that.
The aim is improvement you value, rather than a number that sounded impressive at the consultation.
Why does active acne have to be controlled before treating scars?
If new inflammatory spots are still appearing, new scars may be forming while older ones are being treated. That makes progress harder and adds avoidable damage. Controlling the acne is therefore a priority.
Scar procedures generally begin once it is sufficiently settled, with a plan to reduce further breakouts.
That does not mean everyone has to be completely spot-free for an identical number of months. The decision depends on the acne activity, the treatment area, the procedure and the medicines being used.
It also does not mean you should wait to ask for help. Acne that is causing scars deserves early medical assessment. You do not need to work through every product on the pharmacy shelf first.
NICE recommends specialist assessment for severe scarring that persists a year after acne has cleared. That is a specific referral recommendation, rather than a rule that every scar consultation or treatment must wait a year.
Tell the clinician about current, recent and past acne medicines, including isotretinoin. The timing of procedures needs individual review rather than a blanket rule copied from someone else’s treatment plan.
What does realistic acne scar improvement look like?
A good result might mean that the skin looks less rippled in side lighting, a deep pit draws less attention, or a raised scar becomes flatter and less uncomfortable. The scars may still be visible close up.
That does not mean treatment has failed if the overall change is useful to you.
Treatment often takes place over several months. Some people need a series of sessions; others need a focal procedure followed by time to heal and reassess. The number and spacing should follow the treatment and your response, rather than a package chosen before anyone has examined the scars.
There is another reason not to judge too early: swelling can temporarily make depressions look smoother. The skin looking plumper straight after treatment is not proof of the final result.
Collagen remodelling is gradual. Progress photographs should use consistent lighting, camera position and facial expression. A flattering after photograph and an unforgiving before photograph can make almost anything look successful.
What is reasonable to hope for is softer contours, less obvious shadowing and scars that bother you less. Completely poreless skin, identical texture in every light and guaranteed clearance after one appointment are not sensible promises.
You do not have to treat every scar, and you do not have to decide on a procedure before the consultation.
Further reading
- American Academy of Dermatology: types of acne scars
- American Academy of Dermatology: acne scar treatment
- DermNet: acne scarring
- DermNet: post-inflammatory hyperpigmentation
- DermNet: subcision
- DermNet: TCA CROSS
- NICE: acne management, including acne-related scarring
Where to find us
I see patients at 120 Pall Mall, St James’s, central London SW1Y 5EA, a short walk from Piccadilly Circus, Green Park and Charing Cross.
Patients come to me from across London, throughout the UK and internationally. Acne scarring is assessed individually, because the treatment has to follow the scar rather than the other way round.
Frequently asked questions
What are the four types of acne scarring?
The four main patterns are ice pick, boxcar, rolling and raised scars. Ice pick scars look like tiny, deep punctures. Boxcar scars are round or oval depressions with clearly defined edges. Rolling scars are broader dips with gently sloping edges. Raised scars sit above the surrounding skin and include hypertrophic scars and keloids.
How do you tell an acne scar from a dark mark?
Ask whether the colour has changed, the contour has changed, or both. A flat brown or grey-brown patch may be post-inflammatory hyperpigmentation, and a flat pink, red or purplish mark may be post-inflammatory erythema. A pit, dip or raised patch suggests a structural scar. You can also have colour sitting over a scar.
Can acne scarring be removed completely?
Usually the realistic goal is to make scars less noticeable rather than return the skin to a completely unscarred state. Even surgically removing an individual scar replaces it with another scar, ideally one that is less conspicuous. Resurfacing can soften edges and improve unevenness, but it cannot promise perfectly smooth skin in every light.
Which type of acne scar is hardest to treat?
There is no single hardest scar to treat. Deep pits can be stubborn, while keloids can recur even after an initially good response. Depressed scars are more common overall, and ice pick scars are often described as the most common individual type.
What is subcision?
Subcision involves releasing selected fibrous bands beneath the skin, and may be considered where rolling scars are tethered. In suitable cases it may be combined with filler or followed by treatment for the remaining surface irregularity. Risks include bruising, bleeding, infection, pigment changes and injury to nearby structures.
What is TCA CROSS?
TCA CROSS is a treatment where a clinician applies a concentrated acid precisely to the scar to encourage remodelling, and selected ice pick scars may respond to it. It is very different from applying an exfoliating acid at home, because concentrated acid can cause burns, pigment changes and further scarring if used incorrectly.
Do you have to wait until acne has cleared before treating scars?
Scar procedures generally begin once acne is sufficiently settled, but that does not mean everyone has to be completely spot-free for an identical number of months. NICE recommends specialist assessment for severe scarring that persists a year after acne has cleared, which is a referral recommendation rather than a rule that every scar consultation must wait a year.
Can acne scarring be treated in darker skin?
Darker skin can be treated, but the risk of post-inflammatory pigmentation needs careful consideration. Treatment choice, settings and aftercare should reflect that.
Can you have more than one type of acne scar at once?
Yes. You can have several types at once, and you may need more than one approach, sometimes in stages. A plan might address tethering first, then reassess the surface, with a separate focal treatment for a deep pit. That does not mean everyone needs a long list of procedures.
Where is Dr Nabil Jetha’s clinic?
My clinic is at 120 Pall Mall, St James’s, London SW1Y 5EA, in central London. It is a short walk from Piccadilly Circus, Green Park and Charing Cross, and patients come to me from across London, throughout the UK and internationally.
Who is Dr Nabil Jetha?
I'm Dr Nabil, MBBS, BSc (Hons), PGDip (Aesthetics), GMC 7751313, and I practise aesthetic and skin medicine at 120 Pall Mall, St James’s, central London.
You can check my registration on the GMC medical register using reference number 7751313.
If you are unsure whether you have marks, scars or both, start with an assessment. Knowing what you are looking at makes choosing what to do about it considerably easier.
This article provides general information and is not a substitute for individual medical advice. Treatment suitability, risks and expected outcomes require an individual assessment.
Written and edited by Dr Nabil Jetha and his clinic team. Dr Nabil Jetha, MBBS, BSc (Hons), PGDip (Aesthetics), GMC 7751313. Last reviewed October 2026.