How many gallons does a walk-in tub hold? Water capacity depends on the model and on you: the bather displaces water, so every Ella tub has two numbers, an unoccupied capacity and a typical occupied range. The quick answer: most standard-size Ella walk-in tubs hold 65 to 107 gallons unoccupied, and you will typically use 30 to 75 gallons per bath once you are seated. Our largest tubs, the ShaK, Escape, and Big4Two, hold up to 145 gallons unoccupied.

Capacity by Model (gallons)

Gallon figures are taken from the current spec sheets; the litre conversions printed on some sheets are misprints and are intentionally left out. Monaco, Mobile, and LayDown60 capacities are not printed on the current spec sheets, so please check the live product page or ask the team rather than relying on older figures. The Monaco's occupied range has been given by the team as about 55 to 85 gallons.

What This Means for Your Water Heater

Your house water heater matters as much as tub capacity. The general guidance from our team:

• The average walk-in tub usually calls for a 75 gallon or larger water heater. We recommend the maximum capacity heater available for your house.
• Our largest tubs, such as the ShaK and Big4Two, may require a dedicated additional heater.
• Tankless water heaters should be rated at 11 GPM or more.
• Three quarter inch supply lines with accessible shut-off valves are recommended, and both Ella fast-fill faucet sets include two 5 foot braided supply lines. See water supply lines, shut-off valves and pipe size.
• Other factors matter too: house water pressure, pipe size, the distance from heater to tub, and simultaneous hot water use elsewhere in the home. Have your contractor assess the full picture, and read what size water heater do I need.

This video walks through the hot water question in three steps: use the maximum-capacity water heater available, since under 75 gallons is not recommended, and consider a dedicated or second heater for large tubs like the Big4Two or ShaK; on the website click Compare Ella Walk-In Tubs, then Compare Specs, to see each tub's water capacity in gallons occupied and unoccupied; and run 3/4 inch supply lines with accessible shut-offs, using the 5 foot supply lines that ship with the Ella 2-piece and 5-piece faucets.

Fill and Drain Times

With the Ella fast-fill faucets (2-piece at 16 GPM, 5-piece at 18 GPM, both rated at 60 PSI under ideal in-home plumbing), fill time ranges from 7 to 15 minutes depending on tub size and your water supply configuration; fast-fill faucet expectations explains what changes it. Draining is gravity driven through Ella's dual 4-port 2" drains, which empty an average tub in about 80 seconds under ideal house-drain conditions; see Dual Drain Technology explained. A quick reminder: the in-line water heater maintains your bath temperature while the hydro pump runs, it does not heat cold water, so fill hot from the faucet and let the heater keep it comfortable. The in-line heater article covers what it does and does not do.

Common Questions

Still need help? Open a support ticket at ellasbubbles.com/support and the team will be glad to confirm the exact numbers for your model, or call (800) 480-6850.