A swim spa is a single self-contained unit that combines a current of water you swim or exercise against with a hot-tub soaking section — giving you a pool, a fitness tool, and a relaxation space in a footprint that fits most backyards. If you want to swim laps, do aquatic exercise, or contrast hot-and-cold therapy without the space or cost of a full pool, a swim spa is worth a close look. The brands covered on this site do not manufacture swim spas, but several sell products — including purpose-built contrast-therapy units, hot tubs, and cold plunges — that overlap with what swim-spa buyers are searching for.
What exactly is a swim spa, and how does it work?
A swim spa uses one or more propulsion jets, paddlewheels, or resistance-current systems to generate a continuous stream of water. You swim against the current in place, the same way a treadmill keeps you running without moving across the floor. Most units also have a separate or integrated seating area with hydrotherapy jets for soaking.
The result is a unit that is typically 12 to 20 feet long — far shorter than a lap pool — but deep enough to swim in. Because it is self-contained with its own heater, filtration, and insulation, it can be installed above ground, partially in-ground, or fully in-ground, depending on what your yard allows.
Swim spa versus hot tub versus cold plunge
- Hot tub: designed for soaking and hydrotherapy jets; water is kept at up to 104°F (the limit set by the US Consumer Product Safety Commission); no swim current; typically 6 to 10 feet across.
- Cold plunge: designed for cold-water immersion, typically 50°F or below; no jets for exercise; compact, often 1–2 person capacity.
- Swim spa: adds a propulsion current to enable in-place swimming or water exercise; usually larger, heavier, and more expensive than either a hot tub or a cold plunge alone.
- Contrast-therapy combo: some newer units (see the Chilly GOAT Valaris section below) put a hot-water side and a cold-water side in one shell, giving you something close to swim-spa versatility in a more compact format.
Who is a swim spa actually right for?
A swim spa fits a specific kind of buyer. It suits you well if you want regular low-impact cardiovascular exercise, live in a climate where an outdoor pool is seasonal, or have a yard too small for a full pool. It is also a strong option for households that want one unit for both fitness and relaxation.
It suits you less well if your primary goal is competitive-stroke training at full extension (a full-length pool is better for that), if you want only hot-tub soaking (a standalone hot tub costs less), or if cold-water immersion is your main focus (a dedicated cold plunge is more targeted and typically less expensive).
Health and safety notes
Research suggests that regular heat exposure and regular cold-water immersion may support cardiovascular and recovery outcomes — the Mayo Clinic Proceedings 2018 review summarizes the cardiovascular evidence for sauna bathing, and a 2025 PLOS ONE meta-analysis covers cold-water immersion. Both are observational or review-level; neither proves that a swim spa causes specific outcomes. If you are pregnant, have a heart condition, high or low blood pressure, or take medication, ask your doctor before using any hot-water or cold-water immersion product. The CPSC recommends water temperatures never exceed 104°F; 100°F is generally considered safe for healthy adults. Keep the cover locked whenever children are around. A 240-volt swim spa must be wired by a licensed electrician — do not attempt to wire it yourself.
Key specifications to compare when shopping
Swim spas vary widely in quality, power, and features. Before you call a dealer, know which numbers matter.
Current system and horsepower
The propulsion system determines whether the current feels like a gentle resistance for water walking or a strong enough flow for competitive-style swimming. Most manufacturers rate their jets in horsepower (HP); a single-pump unit at 2–3 HP suits fitness and family use, while serious swimmers typically look for 4 HP or more. Ask the dealer for the pump HP rating and whether the current is adjustable.
Length and water volume
Swim spas range from roughly 12 feet to 19 feet or more. Longer units give more room to extend your stroke. Water volume (in gallons) affects how long the unit takes to heat, how much chemical treatment it needs, and its filled weight — which matters enormously for site preparation. A fully filled swim spa can weigh several thousand pounds; confirm what your pad or deck can support.
Temperature range
Swim spas designed for exercise are often kept around 80–90°F — warm enough to be comfortable but cool enough for sustained effort. Units with a cold side (like the Valaris contrast units below) can go much colder. Confirm the minimum and maximum temperature range before you buy.
Electrical requirements
Most swim spas require 240V service, often at 50 or 60 amps, hardwired by a licensed electrician. Some smaller or inflatable hot tubs plug into a standard 120V outlet (see the Redwood Outdoors Sequoia and Wave Spas entries below). Always confirm the exact circuit requirement with the manufacturer's specification sheet before installation.
Filtration and water care
A larger water volume means more work to keep clean. Look for multi-stage filtration, ozone or UV sanitation, and easy access to the filter housing. Some units include these as standard; others charge extra.
What a swim spa typically costs — and what drives the price
Swim spa prices span a very wide range depending on size, current-system quality, shell material, insulation, and brand. Because the brands covered on this site do not manufacture swim spas, we cannot quote swim-spa-specific prices from our verified facts. What we can tell you is what drives the cost at each end of the range:
- Entry-level units typically use a single-speed jet system, basic insulation, and simpler filtration. They are adequate for water walking and low-intensity exercise.
- Mid-range units add variable-speed current systems, better insulation (which lowers running costs), and more seating options.
- Premium units offer dual-zone hot-and-cold capability, high-horsepower current systems, smartphone controls, and stronger warranties.
- Installation add-ons — a reinforced concrete pad, electrical rough-in, permit fees, landscaping, and a cover lifter — are additional costs that vary significantly by region. Get local quotes for each; we cannot state dollar figures for these services without a verified source.
Running costs depend on your local electricity rate, how often you use the unit, and how well it is insulated. Ask the manufacturer for the heater wattage and the pump wattage, then multiply by your rate per kWh to estimate a monthly figure.
Products on this site that overlap with swim spa needs
None of the brands Hot Then Cold currently covers manufacture a traditional swim spa with a propulsion current. However, several sell products that address the same underlying goals — hot-and-cold contrast therapy, aquatic relaxation, and fitness recovery. Here is how they compare to a swim spa purchase.
Michael Phelps Chilly GOAT Valaris — hot-and-cold contrast in one unit
The Valaris Terrain and Valaris Glacier are the closest products on this site to the dual-zone experience many swim-spa buyers are after. Both models share the same specifications: an 84 x 84 x 30 inch shell with a hot-tub side (150 gallons, up to 104°F) and a cold-tub side (120 gallons, down to 40°F), 18 hydromassage jets, a self-contained chiller, Wi-Fi app control, UV water purification, and LED lighting. Dry weight is 1,010 lbs; filled weight is 3,820 lbs. Power requirement is 240V / 50 amp. Both are priced at $14,995 (as of October 2026; prices change) and are built in the USA of US and imported parts. Delivery is standard two-person home delivery to the contiguous US; additional delivery requirements may result in extra charges. The residential warranty covers the shell structure, shell surface, equipment (control system, heater, pumps), and plumbing for 2 years, with 1 year on LED lighting and the UV system (confirm details at chillygoattubs.com).
Who it suits: buyers who want hot-and-cold contrast therapy in a single outdoor unit with a compact footprint and no separate chiller to plumb. It has 3-person seating and 16 hydromassage jets but no swim current — it is a contrast-therapy and soaking unit, not a lap-swimming machine.
Who it suits less well: anyone who wants to swim laps or train against a propulsion current. For that, a purpose-built swim spa from a pool/spa dealer is the right tool.
Redwood Outdoors Sequoia Wi-Fi Hot Tub — plug-in soaking
The Sequoia Wi-Fi 3-person hot tub is listed at $4,200 (regular $5,999, as of October 2026; confirm current availability at the seller's page — it was listed as out of stock when checked). It plugs into a standard 120V outlet, seats three (two deep seats plus one lounger), has 25 adjustable jets, Wi-Fi digital controls with an app, and UV sanitation. No swim current; this is purely a soaking and hydrotherapy unit. Redwood Outdoors has a 1-year limited sauna warranty from delivery (original purchaser only); confirm hot-tub warranty terms on the product page. Trustpilot: 4.3/5 from 391 reviews, October 2026.
Who it suits: buyers who want a hot tub they can plug in without electrical work — a meaningful cost and logistics advantage. Best for soaking and family hydrotherapy.
Who it suits less well: anyone wanting cold-water immersion or swim exercise capability.
Wave Spas — inflatable and eco-foam hot tubs
Wave Spas offers inflatable and eco-foam hot tubs starting from $404.99 for the Atlantic inflatable (4-person, as of October 2026; prices change). The maximum temperature is 104°F on all models. Inflatable units heat at roughly 2°F per hour and use around 16 kWh per day with regular use — multiply that by your electricity rate to estimate running costs. Wave Spas is rated 4.8/5 from 11,300 reviews on Reviews.io (October 2026) and 3.3/5 from 7,888 reviews on Trustpilot (October 2026). Shipping is free and same-day. No swim current is available on any model.
Who it suits: buyers on a tight budget who want a soaking hot tub they can store away when not in use. The inflatable format is also good for renters.
Who it suits less well: anyone wanting exercise capability, cold immersion, or a permanent installation.
SaunaLife S4N at Select Saunas — wood-burning soak tub
If your swim-spa interest is partly about an outdoor soaking ritual, the SaunaLife Model S4N Soak Series wood-burning hot tub at Select Saunas is worth considering. It is listed at $5,690 (regular $8,632, as of October 2026; prices change) with free continental US shipping and a free sauna accessory package. It seats up to 6 people and is wood-fired, so there are no electrical running costs for heating — though you do need a dry wood supply. Select Saunas accepts HSA/FSA via TrueMed, offers financing, installation services, and a price-match guarantee.
Who it suits: buyers who want the aesthetic and ritual of an outdoor soaking tub without electrical infrastructure, and who enjoy the wood-fired experience.
Who it suits less well: anyone who wants precise temperature control, cold immersion, or swim-exercise capability.
Cold plunges for contrast therapy
Many people searching for a swim spa are really looking for contrast therapy — alternating between hot and cold water. A dedicated sauna plus a dedicated cold plunge replicates that experience, often with more precise temperature control and a lower combined footprint than a swim spa. See our sauna and cold plunge home setup guide and our cold plunge buyer's guide for full comparisons of brands including Renu Therapy, Plunge, Polar Monkeys, and Cryospring — all covered in detail on this site.
Side-by-side: products on this site compared to a swim spa
- Swim spa (purpose-built, from a pool/spa dealer): has a propulsion current for in-place swimming; largest footprint; highest price; requires a concrete pad and 240V hardwiring; best for fitness-focused buyers.
- Chilly GOAT Valaris ($14,995 as of October 2026): hot-and-cold dual zone, 240V/50A hardwired, 3-person, no swim current; best for contrast therapy and soaking.
- Redwood Outdoors Sequoia ($4,200 as of October 2026): 120V plug-in, 3-person, hot only, no swim current; best for easy-install soaking.
- Wave Spas inflatable (from $404.99 as of October 2026): inflatable, 120V, hot only, no swim current; best for budget soaking or renters.
- SaunaLife S4N at Select Saunas ($5,690 as of October 2026): wood-fired, no electrical running costs, up to 6 person, no swim current; best for the outdoor soaking ritual.
- Sauna + cold plunge combo: separate units, precise temperature control on each side, no swim current; best for dedicated contrast therapy.
Installation: what to prepare before delivery
Whether you buy a swim spa, a contrast-therapy unit like the Valaris, or a standalone hot tub, installation preparation is almost always the buyer's responsibility.
Site and surface
Any large water-filled unit needs a level, load-bearing surface. The Chilly GOAT Valaris, for example, fills to 3,820 lbs. A reinforced concrete pad is the most common solution, but a well-built deck rated for the load can also work. Get a structural assessment from a local contractor before committing to a surface — the cost and requirements vary by location.
Electrical
A 240V swim spa or contrast unit requires a dedicated circuit installed by a licensed electrician in compliance with the National Electrical Code (NEC). The Valaris, for example, requires 240V / 50A. The Sequoia hot tub plugs into 120V — a meaningful advantage if you want to avoid electrical work. Get a quote from a local licensed electrician before you finalize your budget.
Permits
Many municipalities require a permit for a permanent outdoor water feature or electrical installation. Check with your local building department; requirements vary widely.
Delivery logistics
Swim spas and large hot tubs are heavy and awkward. The Valaris ships from Fort Wayne, Indiana, with standard two-person home delivery to the contiguous US; additional delivery requirements may incur extra charges. Confirm gate widths, clearance, and access routes before your delivery date.
How to evaluate a swim spa deal or sale
Swim spa retailers frequently advertise large discounts. Before you commit, check these things:
- Compare the sale price against the regular price for the same model, not against a vague "MSRP."
- Confirm what is included: cover, steps, startup chemical kit, and delivery are sometimes bundled and sometimes extra.
- Read the return and cancellation policy in full — most large water-filled units are non-returnable once installed or filled.
- Check the warranty length separately for the shell, the equipment (pumps, heater), and any electronics. The Valaris, for example, has a 2-year warranty on the shell and equipment but only 1 year on LED lighting and the UV system.
- Ask whether the sale price includes delivery and what happens if delivery requires a crane or special equipment.
- Confirm the electrical requirement and budget for installation before the unit arrives.
Common mistakes swim spa buyers make
- Underestimating the filled weight. A unit that weighs 1,000 lbs dry can exceed 3,000–4,000 lbs filled. If your deck or pad cannot support that, you have a serious problem after delivery.
- Forgetting the electrical budget. A 240V / 50A circuit installation involves a licensed electrician, new breaker, conduit, and potentially a sub-panel. Get a quote before you commit to a unit that requires it.
- Choosing size based on max capacity rather than regular use. A 6-person unit costs more to heat and maintain than a 3-person unit. Buy for how many people will use it on a typical day, not a peak day.
- Skipping the water-care plan. Large water volumes need consistent filtration and sanitation. Budget for filters, chemicals or ozone cartridges, and water testing.
- Not measuring the access path. Swim spas are long and wide. Measure every gate, doorway, and turn between the delivery point and the final installation location before you order.
- Ignoring running costs. Ask for the heater wattage and pump wattage, then calculate the cost at your local electricity rate before deciding between a well-insulated premium unit and a cheaper, less-insulated one.
Frequently Asked Questions
What is the difference between a swim spa and a hot tub?
A swim spa adds a propulsion current that lets you swim or exercise in place — it is essentially a short pool combined with a soaking area. A hot tub has hydrotherapy jets for relaxation but no swim current. Swim spas are longer (typically 12–19 feet), heavier, and more expensive than hot tubs, and they require a stronger electrical supply. If exercise capability is not a priority, a hot tub or a contrast-therapy unit like the Chilly GOAT Valaris will likely meet your needs at a lower cost and with a smaller footprint.
Do I need a special electrical circuit for a swim spa?
Most swim spas require a dedicated 240V circuit, often at 50 or 60 amps, hardwired by a licensed electrician in compliance with the National Electrical Code. Some smaller hot tubs (like the Redwood Outdoors Sequoia) plug into a standard 120V household outlet, which is a significant convenience advantage. Always confirm the exact electrical requirement from the manufacturer's specification sheet before purchasing, and get a quote from a local electrician before finalizing your budget.
Can I use a swim spa year-round in a cold climate?
Many swim spas and hot tubs are designed for year-round outdoor use, with insulated shells and covers that retain heat. The key variables are insulation quality (look for the R-value or foam-fill specification), cover quality, and the heater's capacity relative to your typical winter ambient temperature. In very cold climates, running costs will be higher in winter; ask the manufacturer for the heater wattage and calculate the cost at your electricity rate. An insulated cover — and keeping it on when the unit is not in use — significantly reduces heat loss.
Is a swim spa the same as contrast therapy?
Not exactly. Traditional contrast therapy alternates between hot and cold water — for example, a sauna followed by a cold plunge. Most swim spas keep water at one temperature (often around 80–100°F for exercise or soaking). Dedicated contrast units like the Chilly GOAT Valaris have a hot side and a cold side in one shell, which more closely replicates true contrast therapy. If contrast therapy is your primary goal, a sauna-and-cold-plunge combination or a dual-zone unit is more targeted than a standard swim spa.
What should I look for in a swim spa warranty?
Check the warranty length separately for the shell structure, the shell surface finish, the equipment (pumps, heater, controls), and any electronics. Shorter coverage on electronics and LED lighting is common even in otherwise generous warranties — the Valaris, for example, covers the shell and equipment for 2 years but the LED lighting and UV system for only 1 year. Also check whether labor is covered, whether the warranty transfers to a second owner, and what voids it (some sauna warranties are voided by proximity to water, for example). Always read the warranty card or page in full before purchasing.
How much does it cost to run a swim spa?
Running costs depend on your local electricity rate, the heater and pump wattage, how often you use the unit, water temperature, ambient temperature, and insulation quality. We cannot state a dollar figure without a verified source for your specific unit and location. Ask the manufacturer for the heater wattage and the pump wattage, then multiply by your rate per kWh to estimate a monthly figure. A well-insulated unit with a quality cover will cost meaningfully less to run than a poorly insulated one of the same size.
Are there alternatives to a swim spa for home fitness and recovery?
Yes. If lap swimming is the goal, a full-length pool is the most effective option. If recovery and contrast therapy are the goal, a dedicated sauna plus a cold plunge gives precise independent temperature control and is often a better value than a swim spa for that specific use. See our sauna and cold plunge setup guide for a full breakdown, and our cold plunge chiller guide for chiller-powered options. If soaking and hydrotherapy are the goal, a quality hot tub like the Chilly GOAT Valaris or the Redwood Outdoors Sequoia may serve you better at a lower cost and simpler installation.
The bottom line
A swim spa is a strong choice if you want in-place swimming or water exercise combined with soaking, and you have the yard space, site prep budget, and 240V electrical capacity to support it. For most buyers, the decision comes down to whether the swim-current feature is genuinely important — if it is, a purpose-built swim spa from a specialist pool/spa dealer is the right path. If your real goals are contrast therapy, outdoor soaking, or hydrotherapy recovery, the products on this site can get you there at a lower cost and with simpler installation.
- For hot-and-cold contrast therapy in one outdoor unit: the Chilly GOAT Valaris Terrain or Glacier ($14,995 as of October 2026) is the closest product on this site, with a 40°F cold side and 104°F hot side, Wi-Fi controls, and a 2-year residential warranty.
- For easy-install outdoor soaking: the Redwood Outdoors Sequoia ($4,200 as of October 2026) plugs into a standard 120V outlet — no electrician needed.
- For budget soaking or a portable option: Wave Spas inflatable models start from $404.99 (as of October 2026) with free same-day shipping.
- For a wood-fired outdoor soak tub: see the SaunaLife S4N at Select Saunas ($5,690 as of October 2026), which earns free shipping and a price-match guarantee.
- For dedicated contrast therapy (sauna + cold plunge): visit our sauna and cold plunge home setup guide and our cold plunges section for full brand comparisons.
All prices are as of October 2026 from the sellers' published pages — confirm current pricing directly with each seller before purchasing.