Float Therapy: What to Expect in a Sensory Deprivation Tank

Float therapy involves lying in a shallow pool of water saturated with Epsom salt (magnesium sulfate) in a dark, soundproof environment, allowing your body to float effortlessly at skin temperature. A single session at a dedicated float studio typically costs $60 to $90, based on aggregated studio pricing across US markets. A 2018 study published in PLOS ONE found significant reductions in anxiety, stress, and muscle tension following a single flotation session in a sample of 50 participants.

What Is Float Therapy (Sensory Deprivation)?

Float therapy, also called flotation REST (Restricted Environmental Stimulation Therapy), sensory deprivation, or isolation tank therapy, provides an environment with minimal sensory input. The combination of dense salt water, body-temperature water and air, darkness, and soundproofing removes most of the stimulation your nervous system typically processes.

The basic setup: a tank or pod filled with 10 to 12 inches of water heated to approximately 93.5 degrees Fahrenheit (skin-receptor neutral temperature), saturated with 800 to 1,000 pounds of Epsom salt, which makes the water so dense that you float with no effort regardless of body size or shape. The environment is enclosed with a lid or door that you control at all times.

Float tanks were developed in the 1950s by neuroscientist John C. Lilly for research into consciousness and sensory processing. Commercial float studios began appearing in the 1970s and have expanded significantly in the 2010s and 2020s as wellness interest grew and the equipment became more accessible.

What Happens During a Float Therapy Session?

A complete float experience at a dedicated studio follows a standard sequence:

1. Pre-float shower: You shower before entering the tank to remove oils, skincare products, and sweat, which would contaminate the water. Studios provide soap and shampoo.
2. Earplugs: You insert provided earplugs before entering. The salt-saturated water is not harmful to skin, but getting it in ears or eyes is uncomfortable. Many studios provide petroleum jelly to protect small cuts or skin abrasions from the salt.
3. Entering the tank: You step into the shallow pool, sit, and lie back. The salt water immediately takes your weight. Most people report surprise at how effortless floating is.
4. Sensory transition: You turn off the light (or leave it on; you control it) and adjust to the silence. Many people experience an adjustment period in the first 10 to 20 minutes where the mind remains active, awareness of the body surfaces, and it feels like little is happening. This is normal.
5. Deeper relaxation phase: After the initial adjustment, most people describe a transition into deep relaxation. Some experience vivid mental imagery; many report a loss of track of time.
6. Session end: Music or a gentle light signal indicates the end of the session. You shower again to rinse the salt off.

The studio provides towels, a private room, and typically a quiet lounge area for post-float decompression.

Benefits of Float Therapy: What Research Supports

The research on float therapy is more substantive than many wellness trends, though the body of peer-reviewed evidence is still growing and most studies are small.

Anxiety and stress reduction: The 2018 PLOS ONE study by Feinstein et al., which examined 50 participants ranging from healthy volunteers to people with anxiety disorders, found that a single flotation session produced statistically significant reductions in anxiety, stress, muscle tension, pain, depression, and negative affect. The effect was largest in participants with anxiety disorders, leading the researchers to note float therapy's potential as a low-risk adjunct for anxiety management.

Chronic pain and fibromyalgia: A 2016 pilot study published in Evidence-Based Complementary and Alternative Medicine found that individuals with stress-related pain (fibromyalgia, burnout, whiplash, and general muscle tension) reported significant pain reduction and improved sleep quality following a series of float sessions. The study was small (n=37), and the authors noted the need for larger controlled trials.

Athletic recovery: Multiple small studies have examined floatation REST in sport contexts, with some findings supporting improved subjective recovery, reduced muscle soreness, and improved mood following training. The research base here is consistent in direction but limited in scale.

Sleep: Some participants in float studies report improved sleep quality following sessions. The proposed mechanism is the deep relaxation response and reduction in cortisol associated with float REST.

Who Uses Float Therapy and Why?

Float therapy draws from three distinct user groups, based on commercially observed booking patterns and the research literature:

Stress and anxiety management: The largest group. Office workers, parents, and people under sustained high-stress conditions who use float sessions as a recovery tool. The environment removes all external demands and produces measurable relaxation responses.

Athletic recovery: Competitive athletes, including elite performers who have been publicly associated with float therapy, use it as a low-impact recovery tool between training sessions. The Epsom salt (magnesium sulfate) is absorbed transdermally to a degree, providing magnesium, though the transdermal absorption rate of magnesium is debated in the research literature.

Meditation and mental focus: People who find traditional seated meditation difficult report that the float environment makes it easier to achieve a deeply focused or meditative state. The removal of sensory input reduces the stimuli that typically interrupt meditation practice.

Is Float Therapy Safe for Everyone?

Float therapy carries a low adverse event profile for healthy adults based on the published research and commercial operation history since the 1980s. Conditions that warrant caution or consultation:

Do not float without physician guidance if you have:

• Epilepsy or a history of seizures: An unsupervised aquatic environment during a seizure creates a drowning risk.
• Serious open wounds or skin infections: Salt water causes significant discomfort in open wounds and creates infection contamination risk for the shared tank.
• Significant low blood pressure (orthostatic hypotension): The transition from lying to standing at session end can cause dizziness. Let the studio know so staff can assist.
• Incontinence: A practical and hygienic contraindication.

Pregnancy: Consult your physician before floating, particularly in the first trimester. There is no evidence of harm from floating during an uncomplicated pregnancy, but the high magnesium environment is an unknown variable, and lying supine for extended periods is advised against in late pregnancy. Your provider's guidance takes precedence.

How Much Does Float Therapy Cost?

Pricing at dedicated US float studios based on aggregated booking platform and studio listings:

Float therapy is not covered by health insurance, and FSA or HSA funds are not eligible for recreational float sessions. Some float studios that operate under a physical therapy or integrative medicine umbrella may have paths to medical reimbursement for therapeutic uses, but this is uncommon.

For a broader picture of wellness treatment costs in the spa environment, see our average spa treatment prices guide and spa day cost guide.

What to Do If You Feel Claustrophobic During a Float

The enclosed tank is the most common first-timer concern. Practical guidance:

Before booking: Ask the studio whether they offer float rooms as an alternative to enclosed pods. A float room is a room-sized open environment (no lid or door) that provides the same water experience without any enclosure. Some studios only have pods; others have a mix.

At your appointment: Ask for the light to be left on inside the pod for your first session. The purpose of darkness is to remove visual stimulation, but the experience is still beneficial with a low light. Many first-timers find darkness comfortable after a few minutes; others prefer leaving a small amount of light on throughout.

During the session: You are never locked in. You control the lid or door at all times. If you feel uncomfortable, open the pod and sit at the edge. Most people who experience initial discomfort find it passes within a few minutes once the body adapts to the floating sensation.

If you exit early: This is completely fine. You will not be charged extra or made to feel that you did something wrong. Float studios expect that some first sessions end early. Reschedule when you are ready and try again with the light on.

For comparison on how float therapy's relaxation profile compares with other heat and sensory wellness modalities, our infrared sauna benefits guide and sauna vs steam room guide cover the alternatives.

How Often Should You Float to Notice Benefits?

Research participants have experienced meaningful relaxation effects from a single session. Regular users describe cumulative benefits: they reach the deep relaxation state faster in subsequent sessions and find the calming effect carries over further into daily life.

The Float Research Collective, a practitioner-researcher network, notes that most regular float users report achieving the most consistent benefit with a monthly session rhythm, though individual preference ranges from weekly to occasional use.

There is no clinical guideline on float frequency. Unlike some spa treatments that have optimal intervals based on tissue turnover or hormonal cycles, float therapy is limited only by cost and practical scheduling. Try a single session first, note your response, and decide from there.