Full Spectrum vs Far Infrared Saunas

STOP paying up to $1,500 extra for full spectrum because a sales page says the research is behind it. Most infrared sauna studies tested far infrared, and we found none showing that adding near infrared to a sauna adds health benefits.

Here is the short answer. Far infrared saunas use one kind of heater panel and are what the research mostly studied. Full spectrum saunas add near and mid infrared sources, such as halogen lamps, dedicated heaters or LED panels. On matched models from the same brand, full spectrum costs about $500 to $1,500 more. Buy far infrared for value and evidence. Buy full spectrum only if you want the different feel and the budget is there.

We compared matched far and full spectrum pairs from Clearlight, Sunlighten and Sun Home line by line, and checked what each study actually tested.

The Difference in One Table

What “Full Spectrum” Adds

Infrared splits into three bands. The CIE definitions published by IUPAC run from 780 to 1,400 nanometers (IR-A, what sauna brands call near), 1.4 to 3 microns (IR-B, mid) and 3 microns to 1 mm (IR-C, far). Sauna makers use these labels loosely and rarely publish a heater spectrum chart.

A far infrared sauna uses panels that emit mainly in the long band. A full spectrum sauna adds sources aimed at the shorter bands. How much it adds depends entirely on the brand:

• Clearlight Sanctuary: two 500W full spectrum heaters on the front glass (Sanctuary 2 listing).
• Sunlighten Amplify: 3 halogen heaters added to 5 carbon far heaters (Amplify II store page).
• Sunlighten mPulse: SoloCarbon heaters for near, mid and far, controlled by zone (mPulse Believe).
• Sun Home Equinox: 2 full spectrum heaters added to 4 far heaters; the type is not stated.
• Health Mate Enrich 2: a 96-diode near infrared LED panel (Enrich 2).

There is no rule for how much near infrared a cabin needs to use the full spectrum label. Two 500W heaters and one LED panel are very different amounts of energy, so ask the brand what the source is and how many watts it draws. Our infrared sauna guide goes deeper on heater types.

The Real Price Premium, Model by Model

We matched far and full spectrum models from the same brand at the same size, using prices checked October 13, 2026:

Clearlight prices are dealer-listed sale prices. Sunlighten’s Signature II price is the Signature I sale price plus Sunlighten’s $500 size option. Golden Designs list prices for Dynamic run far above real retail prices, so treat that last row as a ratio, not a price (Dynamic collection).

Clearlight also sells a middle path. Its Premier IS-1 lists an optional $500 door heater that adds full spectrum, and the IS-2 lists an optional 300W door heater (Premier IS-1). That lets you start with far infrared and upgrade later, on the same lifetime warranty.

Heat and Running Cost

Full spectrum does not always mean hotter. Cleveland Clinic puts infrared sessions in general at 110F to 135F (Cleveland Clinic). Sun Home rates its full spectrum Equinox to 165F and its far infrared Solstice to 140F. But the far infrared Sun Home Pod is also rated to 165F, and JNH rates its far infrared Ensi+ to 170F, so heat depends more on total wattage and cabin design than on the spectrum label.

Running cost barely changes. The Clearlight Sanctuary 2 draws 2,250W and the Premier IS-2 draws 1,750W. At the US average residential rate of 18.31 cents per kWh (EIA, July 2026), that 500W gap adds about 7 cents to a 45-minute session at full draw. The bigger cost is the purchase price.

Watch the wiring on upgrades. Adding the door heater or red light unit to a Sanctuary 2 raises its requirement from a 120V 20A circuit to a 120V 30A circuit, per its listing. Have a licensed electrician confirm the circuit before you order, and ask whether a permit is needed.

What the Research Actually Tested

This is where the marketing and the evidence split.

Far infrared has a real, if limited, research base. A multicenter Japanese trial of 149 hospitalized heart failure patients found that supervised far infrared sauna sessions (140F for 15 minutes, 10 sessions over 2 weeks) improved six-minute walking distance compared with usual care (Tei 2016). The main endpoint was not met, and this was hospital treatment, not home use.

A 2009 review of far infrared sauna studies found limited moderate evidence for blood pressure and heart failure, evidence against cholesterol claims, and concluded that manufacturers’ claims of numerous benefits are “poorly supported” (Beever 2009). A 2018 systematic review of 40 dry sauna studies, covering both traditional and far infrared (Waon) sessions, found possible benefits but mostly small studies (Hussain and Cohen 2018).

Full spectrum has no sauna-specific evidence we could find. We found no peer-reviewed study testing near or mid infrared sources inside a sauna cabin, and none of the medical sources we use supports a benefit from them. That does not prove they do nothing. It means anyone telling you full spectrum is healthier is getting ahead of the research.

Five Questions to Ask Before You Pay the Premium

Sales pages rarely answer these, so ask the brand directly and get the answers in writing:

1. What is the near infrared source? A heater, a halogen lamp or an LED panel. Each delivers a very different amount of energy.
2. How many watts does it draw? Clearlight publishes 500W per full spectrum heater. Most brands publish nothing.
3. Can you control it separately? Sunlighten’s mPulse lets you run near, mid and far zones separately. Most full spectrum cabins do not.
4. Does it change the circuit? Compare the electrical spec of the far and full spectrum versions, and of any add-on heater.
5. Is the warranty the same? At Clearlight, Sunlighten and Sun Home, the full spectrum and far infrared lines share warranty terms, so the premium buys hardware, not coverage. Check that the near infrared source is covered for the same term as the far panels.

If a salesperson cannot answer the first two, you are paying for a label.

Who Should Pay for Full Spectrum

Full spectrum makes sense if:

• You have tried one and prefer how it feels
• The premium is small for your budget (Sunlighten’s is about $500 on matched cabinets)
• You want a specific feature tied to it, like Sunlighten mPulse zone control

Far infrared makes sense if:

• You want the heat type the studies used
• You would rather put $1,300 to $1,500 toward a better warranty, a cedar cabin or a dedicated circuit
• You are on a budget: the Backyard Discovery Rylan 2-Person is far infrared, cedar, around $1,999 on sale, and links a seat-height EMF report

Our pick for most buyers is a well-built far infrared cabin from a brand with a strong warranty. If you do want full spectrum, see our ranked list of the best full spectrum infrared saunas, and compare the two biggest brands in Sunlighten vs Clearlight.

View at Heal With Heat for Clearlight Premier IS-2 Far Infrared (opens in a new tab) View at Heal With Heat for Clearlight Sanctuary 2 Full Spectrum (opens in a new tab)

Safety Applies to Both

Far infrared and full spectrum saunas carry the same core risks: heat stress and dehydration. Cleveland Clinic says to avoid saunas after a recent heart attack or stroke, and to check with a provider first if you have heart disease, high or low blood pressure, are pregnant, take medications, or have epilepsy. Never use a sauna alone or after drinking alcohol. Harvard Health advises no more than 15 to 20 minutes per session and 2 to 4 glasses of water afterward.

Near infrared halogen lamps get hot and bright, so follow the maker’s guidance on spacing and never touch them. For EMF questions, see our low EMF sauna guide.