Same water, two vocabularies
Physiologically there is no difference. Cold water immersion at 37-59°F does the same thing to your body whether the listing called the tub an ice bath or a cold plunge. The vocabulary split is about equipment: "ice bath" grew up around tubs you cool with bags or blocks of ice, and "cold plunge" is the term the chiller-equipped end of the market adopted. Knowing which side of that line you are shopping on is most of the buying decision.
The ice-cooled path: cheap to start, pay per session
An ice bath in the literal sense is a tub plus ice. The Cold Pod ($99) and the Canuck Portable ($650) are the portable versions; the Canuck Red Cedar Barrel ($2,900) is the durable barrel version with a stainless interior. You add roughly 30-40 lbs of ice per session in warm weather, which runs about $25 a month at four sessions a week if you buy bags, or close to nothing with reusable molds and freezer space.
This path wins on entry price and loses on friction: every session starts with a 15-25 minute cool-down ritual, and the ice cost never ends.
The chiller path: pay once, plunge on demand
A chiller-equipped tub holds your target temperature around the clock, so the "ice bath" needs no ice. The Canuck Portable Bundle ($2,900) is the cheapest all-in-one we vet: the same drop-stitch tub as the bare portable plus a 1 HP chiller with ozone sanitation, on a standard 120V outlet. Its floor is 37°F, a deep cold soak rather than a literal ice-and-water bath. The Plunge All-In ($7,990) is the premium hard-shell version with exact control and filtration.
Electricity runs roughly $15-50 a month depending on climate, and the prep ritual disappears entirely.
Which term should you shop by?
Shop "ice bath" if the budget matters more than the ritual: $99-$650 gets you started, and the total stays low if you make your own ice. Shop "cold plunge" (chiller) if you know you will use it several times a week: the $2,900-$7,990 upfront buys back the 15-25 minutes of prep every single session, which is the difference between a habit that sticks and a tub that sits.
The full math at every tier, including cost per session over three years, is in the cold plunge cost breakdown. To see every tub, ice-cooled and chiller-equipped, side by side, use the comparison table or the chiller-equipped collection.