3 Options for a 20 Gallon Water Storage Tank in 2026

A 20 gallon water storage tank is a useful small reserve for a household or RV. At the CDC minimum of one gallon per person per day, 20 gallons covers four people for five days, by calculation. Choose a tank listed for potable water if you will drink from it. For home storage, several smaller jugs may be easier to fill and rotate than one plumbed tank.

#1. Ameri-Kart 20-Gallon Fresh Water Tank: best for a compact RV space

Ameri-Kart 20-Gallon RV Fresh Water Tank

Our verdict:

Best compact RV tank

Best for a plumbed RV or trailer water supply.

View on Amazon

• Listed for potable water in RVs and trailers
• Cube body: 21 by 17 by 14 inches
• Built-in threaded ports; connecting hardware is separate
• The maker says not to pressurize the tank

Keep in mind: the tank must not be pressurized, and connection hardware is separate.

Product details checked October 2026

This is a tank for a fitted system, so measure the space and plan the fittings first. The listing says it suits potable water, including drinking and cooking. Compare the body shape with the space you can reach for service, rather than picking on capacity alone.

#2. Class A Customs T2000-TO: best for a long, narrow bay

Class A Customs T2000-TO Fresh Water Tank

Our verdict:

Best narrow RV tank

Best for an RV bay that suits a rectangular fresh-water tank.

View on Amazon

• 20-gallon tank listed for potable RV water
• Food-grade material listed as NSF certified
• Rectangular body: 32.5 by 11.75 by 11.75 inches
• Tank only; connecting hardware is separate

Keep in mind: use the maker's connection instructions; metal fittings can damage its plastic threads.

Product details checked October 2026

The different shape is the reason to compare it with the Ameri-Kart. Both hold the same stated amount, but fit different spaces. Leave room around the ports. Check what you need to add for filling, venting and drawing water before buying a bare tank.

#3. Saratoga Farms Jug Set: best portable 20-gallon alternative

Saratoga Farms 5-Gallon Stackable Containers (4-pack)

Our verdict:

Best home alternative

Best for a home reserve you can divide among storage spots.

View on Amazon

• Four 5-gallon containers, 20 gallons in all
• Food-grade, BPA-free HDPE
• Flat tops and bottoms stack; handles for carrying

Keep in mind: this is a set of jugs, rather than a single fixed tank.

Product details checked September 2026

This set makes sense when you want the total supply without installing plumbing. You can rotate part of the stash while keeping the rest sealed. Check that each full jug is manageable for the person who will use it; a handle does not make a heavy load light.

How many days does a 20 gallon water storage tank cover

These are calculated from the CDC's one-gallon daily minimum, assuming the whole 20 gallons is usable:

This is an emergency allowance, not a normal showering or RV-use budget. The CDC advises extra water for pets, pregnant people, illness and hot climates. Deduct that extra demand before calling the tank enough for your trip or outage. Our emergency water planning guide helps set a household target.

Factors to consider when choosing a small tank

We used the CDC's storage guidance and each listing's material, shape and fitting claims. We did not test these by hand. Details come from each listing, so check the current page and manual before you buy.

Start with drinking-water use. A utility tank for a garden has a different job from a potable fresh-water tank. Check the exact model and any hose or tap that will touch the drinking water.

Plan to fill, clean and drain the tank without taking apart the room. The CDC says to sanitize containers before filling. A service route matters as much as a neat fit. Put valves where you can reach them and inspect connections before relying on the stash.

Home storage or RV use

Keep a home reserve where you can get to it during a power cut. The CDC calls for cool storage, shade and separation from toxic chemicals. Label home-filled water with its fill date and replace it every six months under the same guidance. See long-term water storage for the full routine.

An RV tank also needs to fit the vehicle's support and water system. Water alone adds about 167 pounds at this capacity, calculated from USGS density data. Include the tank and other loads when checking the vehicle's limits. A fixed tank is useful for utility work only when the intended liquid matches its listing.

Verdict: 20 gallon water storage tank

A potable 20 gallon water storage tank fits a small fixed system; jugs fit a stash you want to split and carry. Measure the space and work out demand first. Return to the rain water barrel guide for storage and treatment options.

Questions people also ask

How long does 20 gallons last four people?

Five days at the CDC minimum of one gallon per person per day, before extra needs for pets, heat or illness. The calculation and source are below.

Can I connect an RV tank directly to a pressure supply?

Follow its manual. Both RV tanks here are listed as tanks that must not be pressurized; they need the right fill and vent arrangement.