Is a Soda Maker Cheaper? SodaStream vs. CO2 Tank

I drink a lot of sparkling water — enough that my recycling bin looked like a seltzer graveyard every week. So a while back I sat down with a calculator to figure out whether making my own bubbles was actually saving me money. The answer surprised me — and it came with a catch involving a $225 metal cylinder.

Here is the honest math, with real numbers and named sources.

The cost per 2-liter bottle

Let me start with the baseline. Consumer Reports pegs the nationwide average price of ready-made soda at about 80 cents per liter — so a 2-liter equivalent runs you $1.60. Their testing also found that soda makers, factoring out the device itself, all beat that price per liter. But "beats the store" is not the same as "cheapest option" — the spectrum is wide:

Cost per 2-liter bottle, in US cents. Sources: Consumer Reports (80 cents/liter national average); Lazy Man and Money (canister and tank math); Accio market analysis. Flavored costs assume roughly 10 cents of flavor additive per bottle.

The SodaStream canister gotcha

A SodaStream starter kit runs about $129 — the machine, a 60-liter CO2 canister, a bottle, and some flavors, per Edible Manhattan. That sounds like a deal until you understand the canister. The blogger behind Lazy Man and Money measured it: a standard SodaStream canister holds just 14.5 ounces of CO2, good for roughly 60 liters. When it runs dry, you are swapping canisters at roughly $15 a pop, which works out to about 25 cents a liter just for the gas — $0.50 per 2-liter bottle for plain sparkling water, before flavors.

It still beats the store's $1.60. But here is the thing nobody mentions at the demo counter: you will be swapping that tiny canister constantly. My household would burn through one every couple of weeks. The exchange runs are annoying, the per-liter price is only okay, and flavors shrink the gap fast (roughly 20 cents a liter more — $0.90 per 2-liter bottle, still ahead of the store but shrinking).

The $225 CO2 tank hack

Now the good stuff. Lazy Man and Money describes the upgrade path: a 20-pound CO2 tank hooked to your soda maker with an adapter like the FreedomOne. The startup cost stings: roughly $225 total (about $125 for the tank deposit plus $100 for the adapter). But the yield is absurd. A 20-pound tank holds 320 ounces of CO2 — 22 times the SodaStream canister — and makes roughly 1,324 liters. Refills cost $20 to $25, putting the gas at about 1.8 cents per liter: a 2-liter bottle for 3.6 cents, and a flavored 2-liter seltzer for roughly 14 cents all-in, per the blogger's math with True Citrus.

That is about 14 times cheaper per liter than plain SodaStream carbonation, and roughly 44 times cheaper than store-bought soda. Accio's market analysis puts it in context: homemade soda runs 40 to 60 percent cheaper than store-bought long term, with residential breakeven at 6 to 8 months. The blogger's household — serious sparkling-water drinkers — paid off the $225 investment in about 9 months.

Who should buy what (and who should not)

Get a SodaStream if: you want bubbles with zero setup, you drink a few liters a week, and you do not mind the canister exchange treadmill. At $0.50 per 2-liter bottle, you still cut your sparkling-water bill roughly in half versus the store. It is the lazy option, and there is no shame in it.

Get the 20-lb tank hack if: your household goes through 2+ liters a day, you have a storage spot for a 24-inch tank, and you can stomach a $225 upfront cost. At 3 liters a day, you save about $1.50 a day versus the store — the tank pays for itself in about 5 months.

Buy the store stuff if: you drink a can or two a week. The equipment never pays off at that volume, and variety packs from the grocery store are honestly delicious. Not every habit needs optimizing.

The honest warning: do not buy a SodaStream, realize the canister costs are only okay, and then feel trapped. The upgrade path exists — but so does the simplest option, which is not buying a gadget for a problem you do not have.

FAQ

How much does SodaStream really cost per liter? About 25 cents a liter for the CO2 alone, based on a 60-liter canister at roughly $15 an exchange — $0.50 per 2-liter bottle of plain sparkling water. Flavors add about 20 cents a liter. (Lazy Man and Money; Consumer Reports.)

How long does a SodaStream CO2 canister last? About 60 liters per canister — a month at 2 liters a day, or a swap every two to three weeks at 3 to 4 liters a day.

What is the cheapest way to make sparkling water at home? A 20-pound CO2 tank with an adapter: roughly $225 upfront, then about 1.8 cents a liter on refills of $20 to $25 per 1,324 liters — about 3.6 cents per 2-liter bottle.

When does a soda maker break even? Accio puts residential breakeven at 6 to 8 months versus store-bought. The Lazy Man and Money household paid off their $225 tank setup in about 9 months.

Is homemade soda really cheaper than store-bought? Yes, over time. Accio finds 40 to 60 percent long-term savings for home setups versus store-bought, up to 80 percent in commercial use. Consumer Reports confirmed that every soda maker they tested beat the 80-cents-a-liter store average once the device cost was factored out.