Cirkul.

A water bottle people film themselves using

Walk into a Walmart and somewhere in the home aisle is a wall of plastic bottles with little cartridges clipped to their necks. Open TikTok and someone is twisting one open, sipping, and rating the flavor for strangers. Cirkul - the company behind both scenes - sells something that sounds almost too small to matter: a way to flavor your water without sugar, without a mixing spoon, and without buying yet another single-use bottle.

That small thing turned into a billion-dollar company. Cirkul makes a reusable bottle, a line of patented "Sip" cartridges, and a dial that controls how much flavor flows through as you drink. Vitamins, electrolytes, and caffeine are optional. Sugar and calories are not on the menu at all. It is, on paper, an unremarkable category. In practice, people post about it.

Plain water has a marketing problem

Everyone agrees you should drink more water. Almost no one finds it interesting. The drinks that taste good are loaded with sugar; the ones that aren't taste like the inside of a plastic jug. For decades the fix was a workaround - a scoop of powder, a squeeze of drops, a tablet that fizzed and stained. All of them shared one flaw: you committed to a single strength for the whole bottle, and you usually made a mess getting there.

The founders of Cirkul knew the mess personally. Garrett Waggoner and Andy Gay met on the Dartmouth College football team in 2010 - Waggoner at safety, Gay at quarterback. Between practices they kept trying to pour powdered sports mix into the narrow neck of disposable bottles. It spilled. It clumped. It was, by any reasonable standard, a ridiculous thing to be annoyed by.

They got annoyed anyway. The annoyance is the whole company.

Two athletes, one stubborn cartridge

In 2016 Waggoner and Gay decided the answer was not better powder but a different mechanism entirely: a cartridge that sits at the top of the bottle and flavors the water on its way to your mouth. Turn a dial, get more flavor or less. Nothing dissolves into the whole bottle, so the water underneath stays just water.

The idea was elegant. Manufacturing it was not. Beverage companies make bottles or cans, and they told the founders so, repeatedly. "We do bottles or cans - we don't do cartridges," was the standard reply. Cirkul's product fell into a gap nobody was tooled to build.

So they built it themselves. They rented a roughly 4,000-square-foot warehouse in Tampa and assembled the early cartridges by hand. Gay, by his own account, took investor calls from the back room of a department store job he worked to keep the lights on. It was not glamorous, and it was not fast.

One bottle, a hundred decisions

The hardware is simple enough to explain in a sentence: a BPA-free reusable bottle (plastic or stainless steel), a cartridge that clicks into the lid, and a dial. The cleverness is in what the dial lets you avoid. You never commit the whole bottle to one flavor. You never measure. You never throw out a half-finished drink because you mixed it too strong.

From there the catalog does the work. There are over 100 Sip flavors - fruit, tea, lemonade, sweet tea, tropical things - and functional lines that fold in electrolytes, B-vitamins, or caffeine for the people who want their water to also be a sports drink, a multivitamin, or a coffee substitute. All of it lands at zero sugar and zero calories, which is the quiet trick: the indulgence of flavor without the receipt.

Then there is the business underneath. You buy the bottle once and the cartridges forever. A subscription reorders them on a schedule. It is the razor-and-blade model, applied to thirst.

The numbers, and the receipts

Cirkul's growth story is the part skeptics should sit with. The company says it has grown roughly 150% per year since its 2018 launch and has been profitable - an unusual pairing for a venture-backed consumer brand, where growth and losses usually travel together. Third-party estimates put annual revenue in the hundreds of millions.

The distribution proof point is Walmart. After launching nationwide in 2022, Cirkul became one of the retailer's fastest-selling products in its home division by 2023, then crossed the border into Walmart Canada. The cultural proof point is TikTok, where flavor taste-tests turned an unglamorous category into a feed of strangers reviewing cherry limeade.

Make drinking water something people actually want to do

Strip away the funding rounds and the mission is almost childishly plain: get people to drink more water by making it taste like something they chose. Cirkul's bet is that hydration fails not because people don't know they should drink water, but because plain water is a hard sell against everything fizzy and sweet on the shelf next to it.

The reusable bottle carries a second argument - fewer single-use bottles, less sugary soda - though Cirkul wisely leads with taste, not virtue. People rarely change a habit to save the planet. They change it because cherry limeade is right there and it has no calories.

The i9 Sports partnership in 2025, naming Cirkul the official hydration partner of a large youth sports network, is the mission aimed at its most honest market: kids who will drink water if, and only if, it tastes like something.

The next twist of the dial

Cirkul is no longer just a flavored-water company. It is rolling out new beverage brands across coffee, tea, energy, sports, and unsweetened, plus dozens of new flavors, and has talked about smart bottles that track hydration. The strategy is consistent: keep the bottle, keep the dial, keep expanding what can flow through it.

The skeptic's question is fair. A cartridge is easy to copy, and big beverage companies have noticed the category. Cirkul's defense is the same thing that nearly killed it early on - the manufacturing nobody else wanted to do. The company that taught itself to make cartridges by hand now makes that the moat.

Back to the Walmart aisle and the TikTok feed. A few years ago, neither scene existed. Flavored water meant powder and a spilled mess; nobody filmed themselves drinking it. Cirkul changed both - not by inventing thirst, but by handing people a dial and letting them decide, sip by sip, exactly how their water should taste. That is a small thing. Small things, turned often enough, become billion-dollar ones.