What is the best tub for a DIY cold plunge?

For most DIYers, the Rubbermaid 50-gallon stock tank ($130) is the best choice - cheap, food-grade, structurally rated, and has the largest accessory ecosystem. For turnkey builders who want pre-installed insulation and chiller ports, The Cold Pod 85-gal ($299) is the best value. For maximum cost-per-gallon, a converted chest freezer is unbeatable at $50-200 used.

Can I use a regular bathtub for a cold plunge?

Functionally yes - any vessel that holds water and fits your body can work as a cold plunge. But standard bathtubs have poor insulation (cold loss is fast), small water volume (usually 40-50 gal, but you're displacing most of it), and plumbing that's not designed for continuous cold water. A dedicated plunge vessel is much better.

How much does a cold plunge tub cost?

Rubbermaid 50-gal stock tank: $130. The Cold Pod 85-gal insulated: $299. Chest freezer (used): $50-200. Pre-built commercial plunge tub: $500-1,500 (vessel only). Full commercial plunge system: $5,000-12,000. For DIYers, the $130-300 range delivers excellent value.

Best Cold Plunge Tub: Complete Buyer's Guide (2025)

How to choose the right vessel for your DIY cold plunge

The vessel is the most visible component of your plunge. It determines how much water you need (and therefore how powerful your chiller needs to be), how big you can be as a user, and where in your home the plunge can live. This buyer's guide covers everything you need to know.

Quick comparison

Option	Cost	Capacity	Position	Best for
Rubbermaid 50-gal stock tank	$130	50 gal	Seated upright	Budget DIY
The Cold Pod 85-gal	$299	85 gal	Seated upright	Turnkey insulated
Chest freezer (converted)	$50-200	30-80 gal	Lying down	Maximum value
Pre-built plunge (commercial)	$5,000+	70-150 gal	Seated	Plug-and-play

The Rubbermaid 50-gallon stock tank — best overall

The Rubbermaid Commercial 50-Gallon Structural Foam Stock Tank is the most popular DIY plunge vessel — and for good reason. At $130, it's the cheapest food-grade vessel that's structurally rated to hold a person's weight. The 50-gallon size fits a seated adult up to about 6'2", and the rectangular shape fits through standard doorways.

Pros:

Cheapest food-grade option
Structurally rated for livestock (won't crack under person's weight)
Fits through standard doorways
Largest accessory ecosystem (covers, ozone ports, bulkhead fittings)
UV-stable plastic lasts 10+ years

Cons:

No built-in insulation (you add your own)
No pre-drilled ports (you drill your own)
Rustic agricultural aesthetic
Sharp rim edges (add foam pipe insulation)

The Cold Pod 85-gallon insulated tub — best turnkey

The Cold Pod 85-Gal Round Tub is the turnkey choice. At $299 it's more than twice the price of the Rubbermaid, but it comes with full-wrap insulation, a matching insulated cover, and pre-installed fittings for chiller plumbing. Just connect your chiller and you're ready to fill.

Pros:

Full-wrap insulation (no DIY insulation needed)
Pre-installed chiller ports (no drilling)
Matching insulated cover included
Larger capacity (85 gal)
Cleaner aesthetic than stock tank

Cons:

2.3x more expensive than Rubbermaid
Round shape less space-efficient than rectangular
700+ lbs when filled (verify floor can handle)
Smaller accessory ecosystem

Chest freezer conversion — best value

For maximum value per dollar, converting a used chest freezer is hard to beat. Pick up a 5-7 cubic foot freezer on Facebook Marketplace for $50-150, line it with a food-grade PVC pond liner, fill with water, and use the freezer's own compressor — controlled by an Inkbird ITC-308 — to maintain temperature. Total build cost: typically $400-600.

Pros:

Highest value per dollar
Excellent built-in insulation
Uses freezer's own compressor (no separate chiller)
Appliance aesthetic (can be hidden)
Lid closes securely (child safety)

Cons:

Horizontal position (lying down)
More DIY work (liner, wiring, lid modification)
Limited to 5-7 cu ft interior volume
Freezer compressor is louder than purpose-built chillers

See our chest freezer build guide for complete instructions.

Commercial pre-built plunges — when to consider

Brands like Plunge, Morozko, and Cold Tub sell complete plunge systems for $5,000-12,000. The premium buys:

Polished controls and aesthetic finish
Customer support and warranty
Delivery and installation
Plug-and-play setup (no DIY work)

What you don't get: better cold therapy. The cold water is the same temperature as a DIY build. For most people willing to spend a weekend building, DIY is 5-15x better value. See our budget guide for the full comparison.

How to choose

Choose Rubbermaid stock tank if:

You're on a budget ($130 vessel)
You want to customize your build
You have space for a visible plunge
You're willing to add your own insulation

Choose The Cold Pod if:

You want a turnkey insulated vessel
You don't want to drill your own ports
You have a 1/2 HP or larger chiller
Your floor can handle 700+ lbs

Choose chest freezer conversion if:

You want maximum value per dollar
You're comfortable with DIY
You prefer lying-down plunge position
You can find a cheap used freezer locally

Choose commercial pre-built if:

You have $5,000+ to spend
You don't want to do any DIY work
You want warranty and customer support
You need delivery and installation

📏 Size matters

For one person, 50 gallons is the sweet spot - enough water to submerge to your waist/chest, small enough to cool efficiently. For two people or for full-body immersion, step up to 80-100 gallons. Beyond 100 gallons, your chiller needs to scale up significantly (1+ HP) and your floor needs to handle 800+ lbs of water.

📚 Continue your build

Once you've picked your vessel, head to our master DIY build guide for plumbing, wiring, and chiller installation. See also our chiller buyer's guide.