How Many Laser Sessions for Armpits?

Everything You Need to Know Before Starting Underarm Laser Hair Removal

If you shave your underarms regularly and deal with razor burn, you already know how frustrating the routine of unwanted hair removal can be. Underarm laser hair removal changes everything. It gives you smoother skin for the long haul and cuts down your weekly grooming time more than almost any other laser treatment area. Once people experience that kind of convenience, they rarely go back to shaving.

But before anyone books their first appointment, the same question always pops up:

How many laser sessions for armpits does it actually take?

The honest answer depends on your hair color, texture, skin tone, hormones, and whether you stay consistent. Most people fall somewhere between six and twelve sessions, which sounds like a wide range, but it makes more sense once you understand the laser hair removal process.

 

How Many Laser Sessions Are Needed for Armpits?

Most clients fall within the 12-16  laser hair removal treatment sessions, usually spaced six to eight weeks apart. The underarm area often responds surprisingly fast because the hairs tend to be darker, coarser, and richer in pigment. Darker pigment equals better laser targeting.

Not everyone responds at the same pace, though.
Some people see thinning almost immediately, while others make steady progress but need more time for noticeable results. Here are a few reasons your laser hair removal journey might be longer:

• Your hair grows very fine or very light
• Your underarms are influenced by strong hormonal patterns
• Your follicles naturally produce denser or more stubborn growth
• Your laser hair removal technician will evaluate your hair follicles at each visit and adjust your personalized treatment plan accordingly.

 

Why You Need Multiple Sessions

Unwanted hair grows in a repeating cycle, and every follicle moves through that cycle at its own pace. At any given time, only a fraction of your underarm hair sits in the right stage for the laser to disable it.

To understand why you need multiple sessions, it helps to know what the full cycle looks like and how long each stage lasts.

The Full Hair Growth Cycle

The complete cycle for underarm hair usually lasts several months, but each stage varies in length and function. This cycle repeats itself continuously, which is exactly why laser treatments work best over time.

Let’s break down each phase:

1. Anagen — The Active Growth Phase (Lasts 2–4 weeks in underarms)

This is the most important stage for laser hair removal.

During anagen:

• The follicle actively produces hair.
• The hair shaft attaches firmly to the follicle.
• Melanin (pigment) concentrates in the hair root.
• The laser can track that pigment and deliver energy directly to the follicle.

Only in this stage can the laser permanently reduce hair growth.
Underarm hair has a shorter anagen phase compared to areas like the scalp, which is part of why this area responds quickly to laser hair removal treatment.

At any time, only 10–20% of your underarm hair sits in anagen. This means a single session only disables that portion.

2. Catagen — The Transitional Phase (Lasts about 2–3 weeks)

Catagen acts like a “shut-down sequence.”

During this stage:

• The hair stops growing.
• The follicle shrinks.
• The connection between the hair shaft and the root weakens.
• Pigment levels decrease.

Because the follicle detaches from the hair, the laser can’t transfer enough heat to disable the follicle. Even if you zap the hair during catagen, the follicle remains intact.

Catagen is brief, but follicles pass through it independently. This randomness is part of why you never hit 100% of follicles in one treatment.

3. Telogen — The Resting & Shedding Phase (Lasts 6–8 weeks)

Telogen is the longest stage for underarm hair.

During telogen:

• The follicle rests under the skin.
• The old hair either sheds or hangs loosely.
• A new hair begins forming beneath the surface.
• The follicle has almost no pigment for the laser to target.

Even though you might see hair in this stage, it’s not actively attached or growing, so it doesn’t respond to laser energy.

After telogen ends, that follicle re-enters anagen and the cycle begins again. This is why hair seems to “grow back” between sessions, even though each laser treatment reduces the total number of active follicles.

 

What Affects Your Total Number of Sessions

Not everyone’s underarms behave the same way. Several factors shape how many sessions you’ll need and how quickly you’ll see noticeable results.

Hair & Skin Characteristics

Your hair color plays a major role. Dark hair absorbs laser energy with incredible efficiency. Blonde, red, or gray hair contains less pigment, so many laser removal clinics won’t treat these colors.

Hair thickness matters, too. Coarse, dense underarm hair usually reacts quickly, while very fine hair takes more visits to break down.

And then there’s skin tone. Your technician uses the Fitzpatrick scale to determine the safest settings.
Light skin with dark hair? You’ll probably see fast changes. Medium and deeper skin tones need different laser types or wavelengths to protect the skin and target the hair follicles effectively.

Hormonal Factors

Your underarms fall into the same category as the face and bikini line: hormone-influenced zones. Hormonal shifts, PCOS, postpartum changes, adrenal imbalances, and genetics can all stimulate new growth even after several laser hair removal sessions. If that’s your experience, you’re not doing anything wrong. Your provider simply works maintenance sessions into your treatment plan so you keep seeing progress.

Consistency

If you push your appointments too far apart, you’ll miss the ideal hair growth windows. When you stay consistent, you:

• Catch more follicles in the anagen phase
• Build stronger results with each visit
• Maintain smoother skin between sessions

It’s like momentum. Once you build it, everything gets easier.

 

What Results Look Like at Each Stage

Everyone progresses at their own pace, but most people see a predictable pattern.

Sessions 1–2: Early Shifts

You’ll notice shedding about one to two weeks after your first laser hair removal session. The hair falls out easily. Regrowth becomes patchy. The skin feels smoother than it did before, even if hair still appears in some spots. It’s the first sign that the laser hair removal treatment worked.

Sessions 3–6: Clear Progress

After the sixth laser hair removal session, most people say they barely shave between appointments. Hair regrowth comes in slower, thinner, and softer. Ingrown hairs drop off dramatically. Irritation fades, especially if shaving previously caused bumps or redness.

Sessions 7–12: Long-Term Reduction

This stage brings the biggest payoff:

• Coarse hairs vanish
• Remaining strands turn wispy or nearly invisible
• Shaving becomes occasional instead of daily
• The skin tone evens out and feels smoother

Anyone who has had Brazilian laser hair removal or bikini laser treatments often notices that the underarms reach the “final phase” sooner because the follicles here typically respond more quickly.

 

How Long Do Underarm Results Last

Once you finish your initial number of sessions, you’ll enjoy smoother skin for a long time. Some people hardly ever see regrowth. Others come in once or twice a year for maintenance. That depends on:

• Hormones
• Stress
• Medications
• Genetics
• Pregnancy or postpartum shifts

Your follicles never “undo” the effects of laser hair removal. Hormones can activate dormant follicles later, but maintenance visits keep everything under control without starting from scratch.

 

How Long will Other Laser Hair Removal Treatment Areas Take

Not every part of the body responds the same to laser hair removal. Different areas have different hair densities and follicle depths, which influence how many sessions you’ll need for long-term reduction.

Brazilian & Bikini Areas

These zones fall into the same hormonal category as underarms, but the hair here tends to be coarser and more densely packed. Most people need:

• 12-16 sessions for a full Brazilian
• A few extra visits if they have hormonally driven hair growth or PCOS

Because of the thickness and depth of the follicles, the bikini region often needs more cumulative laser hair removal sessions than the underarms, even though the hair itself responds well.

Legs

Legs usually respond beautifully, especially if your hair is dark. They do, however, have a much longer anagen phase, so treatments are spread farther apart, often every 6–8 weeks instead of 4–6. We start with sessions every six weeks, and then move to eight weeks apart near the end of treatment.

Average timelines:

• Lower legs: 12-16 sessions
• Full legs: 12-16 sessions

Clients often notice significant reductions in hair growth early in their laser hair removal journey, but full results take time due to the extended hair growth cycle.

Arms & Forearms

Arm hair varies wildly. Some people have fine, light hair that takes more sessions, while others have darker, more responsive follicles.

On average:

• 12-16 sessions

Fine or light-colored hair tends to require more consistent maintenance because it contains less pigment for the laser to target.

Face & Neck

Facial hair grows quickly but rests in very short anagen phases, especially along the jawline or chin. These areas are also extremely hormone-sensitive.

Typical range:

• 12-16 sessions
• Maintenance every few months for some people

People with PCOS or adrenal-driven facial hair often need a personalized treatment plan with long-term maintenance for long-lasting hair reduction.

Back & Chest

These areas have thick, rooted follicles and broad coverage. Because of the sheer density and hormonal influence (especially for men), the number of sessions increases.

Most clients need:

• 12-16 sessions, sometimes more

The good news: reductions are dramatic once the area starts responding.

Stomach & Happy Trail

These areas respond well to laser hair removal but behave differently depending on hormonal patterns.

Typical sessions:

• 12-16

Hair can range from very fine to coarse, making this zone unpredictable but usually manageable with a well-structured plan.

Why Each Area Has a Different Timeline

The differences come down to:

• Follicle depth
• Hair thickness and color
• Sensitivity to hormonal changes
• Length of each growth phase
• Natural density of hair follicles

Laser settings shift with each area, too. Your technician uses different wavelengths, pulse widths, or energy levels depending on your skin and hair characteristics.

A full-body laser hair removal client might finish their underarms quickly, but may still need multiple sessions on their face months later. That’s normal. Every treatment area plays by its own biological rules.

 

Why People Love Laser Hair Removal

Laser hair removal doesn’t just reduce unwanted hair; it transforms the skin.

A few things clients rave about:

Ingrown hair relief
No thick surface hair = no inflamed follicles or ingrown hairs.

Smooth, soft skin
Without daily shaving or razor burn, skin feels healthier and looks more even.

Less odor
Hair traps bacteria. Less hair means fewer places for odor to cling.

Saves time
You stop buying razors, booking waxes, or shaving in the shower.

Confidence boost
Especially for people who deal with irritation or dark underarm shadows from shaving.

 

How to Prep for Your Appointment

You don’t need to overhaul your routine to prep for laser hair removal, just focus on a few practical steps:

• Shave the area within 24 hours of treatment
• Skip deodorant on the day of your appointment
• Pause exfoliants and retinoids for seven days prior to treatment
• Avoid waxing or plucking beforehand because you need the follicle intact
• Avoid sun exposure on the area near your underarms

These small steps help you get the most from every laser hair removal treatment.

 

What Happens During and After a Laser Hair Removal Session

The appointment itself flies by. Underarm laser hair removal treatments take about five to ten minutes. The laser pulses feel like quick snaps against the skin. Most people tolerate it easily because the sensation only lasts a moment.

Afterward, expect a little warmth or redness that calms down within a few hours.

Call for a Consultation

If you’re unsure how your hair and skin will respond to laser hair removal or if you want expert guidance, a consultation gives you clarity. You’ll get:

• A skin and hair analysis
• A personalized treatment plan
• An estimate of how many sessions you’ll likely need
• Safety recommendations, including how to avoid sun exposure
• Room to ask questions about comfort and timing

A good consultation helps you understand exactly how laser hair removal works for your body, so you can start your hair removal journey with confidence.

 

Common Questions About Underarm Laser Hair Removal Sessions

Does laser hair removal hurt?
Most people describe the feeling as a fast rubber band snap. It’s quick and manageable.

Can I wear deodorant after a laser treatment?
Usually, yes, within 24 hours. As long as the area is not red and irritated, it’s safe to use. Make sure to use a gentle deodorant. Don’t use deodorant with acids like AHA.

Does laser hair removal affect sweat glands?
No. The laser only targets hair follicles, not sweat glands. You sweat the same amount; you simply reduce the hair that traps bacteria.

Is it safe for deeper skin tones?
Absolutely, laser hair removal is safe for all skin tones. Your provider will help ensure your treatment is customized for your skin tone and hair texture.

How many sessions do I need to notice results?
Most clients see changes after the first few laser hair removal sessions, with the most dramatic improvements happening between sessions three and six.