Fractional CO2 Laser vs Subcision

Fractional CO2 Laser: An ablative laser that vaporizes thousands of microscopic columns of skin, leaving untouched skin between them to heal from. It is the most effective in-office treatment for indented acne scars, and the one with the most downtime and the highest pigment risk.

Subcision: A needle passed under an indented acne scar to cut the strands holding it down, so the surface can lift. It is aimed at rolling scars specifically, it bruises, and it is almost always combined with something else.

Reviewed by Dr. Schwarz, Board-Certified Dermatologist
Last updated: 10/22/2026

Editorial illustration for Fractional CO2 Laser, based on the entry’s treatment or equipment reference.

Editorial illustration for Subcision, based on the entry’s treatment or equipment reference.

Choose if Key differences What is it?What it treats Treatment areas Skin tones How it works Before your treatment Day of treatment After your treatment Risks Cost Questions Related

Choose Fractional CO2 Laser if…

Choose for the biggest single improvement in indented acne scars or deep sun damage, accepting the most downtime and pigment risk.

Boxcar or rolling acne scars
Deep sun damage or wrinkles
You can take a week or more off

Choose Subcision if…

Choose for rolling acne scars that are tethered down, usually combined with needling, laser or filler.

Soft, wavy rolling scars
Scars that improve when you stretch the skin
You can hide a week or two of bruising

Often combined

Can you have both?

A common acne-scar pairing: subcision releases tethered scars and CO2 smooths the surface. They are usually spaced several weeks apart.

Key differences

● Fractional CO2 Laser

● Subcision

DowntimeNone → 2+ weeks

1–2 weeks

PainMinimal → Needs anesthesia or sedation

Needs anesthesia or sedation

Moderate

Results showImmediately → 3+ months

1–3 months

How long it lastsWeeks → Years or permanent

Years or permanent

Visits neededOne → Every few months

A short series (2–3)

Cost per visit$ → $$$$$

$$$$

ReversibleYes, can be undone → No, permanent

No, permanent

What is it?

Fractional CO2 Laser

Subcision

What is it?

It is an ablative laser.

It creates microscopic columns of injury in the skin.

Untreated skin speeds healing.

Skin between the columns supports recovery.

It is intensive.

It is stronger than a facial but less than fully ablative resurfacing.

History matters.

Pigment, keloid, herpes and isotretinoin history need assessment.

It releases scar bands.

Fibrous bands tethering depressed scars are cut beneath the skin.

It suits rolling acne scars.

It is not for every pit, mark or raised scar.

It is minor surgery.

It is performed by a clinician with a needle or blade.

History is reviewed.

Bleeding risk, scarring tendency and isotretinoin use are assessed.

What it treats

Evidence level

Fractional CO2 Laser

Subcision

Strong evidenceMost established uses

Acne Scarring

Major improvement in many scar types.

Educational illustration of healed broad indented scars with defined edges on the left cheek, with the face turned to the person’s right on light skin.

Boxcar Scars

Smooths wide scars.

A relaxed forehead with faint shallow horizontal fine lines.

Wrinkles and Fine Lines

Tightens and smooths.

Rolling Scars

Releases tethered scars.

Moderate evidenceSome supportive research

Sun Spots

Clears sun damage.

Acne Scarring

Best for rolling scars.

Educational illustration of natural shallow dimpling of adult lateral-thigh skin below the hem of shorts on light skin.

Cellulite

Releases dimples.

Little evidence

—

Boxcar Scars

Better treated with resurfacing.

Not effective

—

Ice Pick Scars

Too narrow to release.

Can make it worse

Flat tan patches with soft irregular edges across the forehead and upper cheek of an adult with light skin, the surface completely smooth.

Melasma

High risk of darkening.

Redness and fine superficial vessels across a light-skinned cheek and nose.

Rosacea

Can worsen redness.

—

Treatment areas

Face; the selected area depends on the concern and treatment plan.

Selected facial scars; the highlighted cheeks show the general treatment area.

Skin tones

Skin tone

● Fractional CO2 Laser

● Subcision

Lighter skin

Some risk

Prolonged redness possible.

Low risk

Bruising.

Medium skin

Higher risk

Dark marks are common; pre-treatment helps.

Low risk

Bruising may leave brief dark marks.

Deeper skin

Higher risk

Highest pigment risk of these treatments; low-density settings and an experienced provider are essential.

Low risk

One of the lower pigment-risk scar treatments.

How it works

Fractional CO2 Laser

Subcision

How it works

Fractional CO₂ Laser mechanism diagram. Creates tiny treatment channels: Laser energy absorbed by water removes narrow columns of tissue. Untreated skin supports healing: Skin between the channels helps the surface repair. Collagen remodels over time: Repair can improve selected scars, lines, and texture.

Subcision mechanism diagram. A scar is tethered below skin: Fibrous bands can pull a rolling scar downward. The bands are released: A clinician passes an instrument beneath the scar. Repair follows the release: The depression may improve as the tissue heals and remodels.

Diagram explanation

Creates tiny treatment channels: Laser energy absorbed by water removes narrow columns of tissue. Untreated skin supports healing: Skin between the channels helps the surface repair. Collagen remodels over time: Repair can improve selected scars, lines, and texture.

Schematic illustration. Technique and response vary. This explains a mechanism and does not specify treatment settings.

A scar is tethered below skin: Fibrous bands can pull a rolling scar downward. The bands are released: A clinician passes an instrument beneath the scar. Repair follows the release: The depression may improve as the tissue heals and remodels.

Schematic illustration. Technique and response vary. This explains a mechanism and does not specify treatment settings.

Before your treatment

Fractional CO2 Laser

Subcision

Earlier planning

Not specified

6 months before: After isotretinoin: Most providers wait about 6 months before subcision, though this is debated and some treat sooner.

2–4 weeks before

Sun and pigment cream: No sun, and do not arrive tanned.

Sun and pigment cream: On deeper skin tones a pigment-blocking cream usually starts two to four weeks ahead.

Plan ahead: Time off and supplies: Book the time off, arrange a driver if sedation is planned, buy plain petrolatum and a gentle cleanser, and plan a week at home.

2 weeks before: Sun: Keep the area out of the sun and use SPF 30 or higher.

Before you book: Timing: Get active acne under control first, or new scars form beside the treated ones.

The week before

Actives and smoking: Stop retinoids, benzoyl peroxide and acids.

1 to 2 days before: Antiviral tablets: Antiviral tablets start a day or two before and continue for several days after, since an outbreak in healing skin can scar.

Actives and supplements: With your prescriber's agreement, stop blood-thinning supplements such as fish oil, vitamin E and ginkgo.

Day of treatment

Fractional CO2 Laser

Subcision

Arrival & prep

Skin is examined and photographed.

Photographs first, then the skin is stretched and lit from the side so tethered scars stand out.

Treatment

The handpiece is passed or stamped over each zone.

Expect rapid clicking, a burning smell, and a smoke evacuator running. Heat builds fast and feels hot rather than sharp. A full face takes 30 to 60 minutes, genuinely painful without proper anesthesia. The burning carries on for an hour or two.

A tiny entry point is made beside the scar, and the needle or cannula is passed underneath and moved side to side in a fan until the skin releases.

You feel pressure, tugging and a faint crunching as the strands give way. Firm pressure follows to limit bruising, and filler or microneedling may follow. Usually 15 to 45 minutes, and once numb it is pressure, not pain.

Before you leave

Skin is deep red, hot, swollen and weeping clear fluid, with a fine grid pattern visible.

Swollen, red and firm, with the treated scars looking temporarily better from the swelling.

After your treatment

Fractional CO2 Laser

Subcision

First 24 hours

Days 1 to 3: Swelling peaks on the first or second morning and can partly close the eyes.

Days 1 to 3: Deep purple bruising appears and spreads downward with gravity, worst around day two or three.

Days 2–7

Days 3 to 14: The skin turns bronze or grid-patterned brown, then flakes and sheets off, showing bright pink skin.

Days 4 to 14: The bruises turn green and yellow, and concealer covers them reasonably well from about day three, once the entry points have sealed.

Weeks 2–4

Week 3 to Month 12: Redness fades slowly, a month on light settings and three months or longer on aggressive ones.

Weeks 2 to 12: Small firm lumps can be felt as the scar tissue remodels, and most soften on their own.

Time to results

1–3 months, improving to 6

1–3 months

How long results last

Years

Long-lasting

Risks

Dark patches
Redness that will not settle
Pale or white patches
An acne or milia flare
Itching that is severe

A firm lump that is growing
Bruising that keeps expanding
A new brown mark
A cold sore outbreak
A scar that looks deeper afterward

Cost

Per session

A full-face session in the US usually runs $1,000 to $3,000, varying by city, device, depth, and whether sedation or an operating room is involved.

In the US, subcision commonly runs a few hundred dollars per session, and the price rises when filler, microneedling or radiofrequency needling is added — filler is often the larger part of the bill.

Insurance

Insurance does not cover resurfacing for acne scars, which is classed as cosmetic.

Insurance almost never covers subcision for acne scars, because scar treatment for appearance is cosmetic.

Questions

Fractional CO2 Laser

Subcision

Individual Questions

How much downtime does fractional CO2 really need?

Five to ten days at home. Swelling and oozing days one to three, bronzing and sloughing days three to seven, and by day seven to ten the surface has closed and mineral makeup is usually allowed. Redness then fades over weeks to a few months.

Will it get rid of my acne scars?

It improves them substantially, more than any other single treatment, but it does not remove them. Rolling and boxcar scars respond best, icepick scars least, and mixed scarring usually needs subcision or TCA CROSS too.

Is it safe on deeper skin tones?

Experienced providers do it using lower density, longer intervals, and pigment creams before and after. Dark marks are common and fade over months. The rare risk of permanent pigment loss is why many people with deeper skin tones choose microneedling instead.

How many sessions will I need?

One to three, 6 to 12 weeks apart, judged six months after the last one.

Does it hurt?

Yes, without proper anesthesia. Numbing cream alone is not enough for a full face, so nerve blocks, injected anesthetic or oral sedation are standard, and burning continues for an hour or two afterward.

Can I have it before a wedding or a big event?

Only with months of margin. Skin looks worse before it looks better, and redness can last one to three months. Six months ahead is a reasonable minimum.

How do I know if my scars are the right type?

Stretch the skin either side of the scar, or press gently beside it. If the dip flattens out, it is tethered, and that is the scar subcision treats. Scars with sharp punched-out edges that stay put when you stretch are icepick or boxcar scars and need something else.

How long does the bruising last?

Usually 7 to 14 days. It looks worst around day two or three, then turns green and yellow, and concealer works from about day three. Plan for two clear weeks, not one.

Will one session be enough?

Usually not. Most courses are 2 to 4 sessions, 4 to 8 weeks apart. Some of the immediate improvement is lost as cut strands reattach, and the gain builds over the course.

Do I need filler with it?

Not always, but many providers add it. Filler holds the released space open while new collagen forms, which reduces retethering. Ask what would be used, how much, and what it adds to the cost.

Does it hurt?

The numbing injections sting for a few seconds and are the worst part. After that it is pressure and tugging, not sharp pain. The area is sore for a day or two, like a deep bruise.

Is it safe on deeper skin tones?

Yes, and it is often a good choice, because it uses no heat or light. The thing to manage is a temporary brown mark where the bruising was. Sun protection, limiting the bruising and spacing sessions all help.

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