How to Make Sun Tea — and Why the Refrigerator Does It Better

Sun tea is iced tea brewed by putting tea bags or loose leaves in a large glass container of water and leaving it in the sun for hours. The Wikipedia entry on iced tea sums up its two genuine advantages: it often gives a smoother flavor, and it uses no electricity or fuel.

The smoothness has a simple explanation. Hot water extracts everything in the leaf quickly, including the bitter, astringent compounds that make over-steeped tea harsh. Warm water extracts more slowly and more gently, so the same tea bags give a rounder, softer drink. A 2015 study in the Journal of Food Science and Technology (Lantano et al.) comparing steeping methods found hot infusion extracted compounds rapidly, while cold infusion worked far more slowly over a long steep — the same principle, taken all the way down to refrigerator temperature.

That is the important point for anyone deciding how to make sun tea: the smooth taste comes from the low temperature and long time, not from the sunlight itself. Sunlight is just a free, imprecise heater. The refrigerator gives you the same slow extraction at a temperature that keeps bacteria in check, which is why the rest of this guide keeps steering you toward it.

Our cold brew tea hub explains how temperature and time trade off.

Safety callout. Ohio State University Extension's food-safety guidance says making tea by leaving it in the sun is “highly discouraged.” Sun tea “will not get hotter than 130 degrees Fahrenheit,” which is “not hot enough to kill bacteria in the water or in the tea leaves,” and it “generally sits around at room temperature for a long period of time.” The bacterium most often named is Alcaligenes viscolactis, a “ropy” bacterium “commonly found in soil and water.” The same guidance adds that this holds “even if the statistical risk of illness is not great.”

The US Centers for Disease Control and Prevention (CDC) explains why time and temperature matter so much: bacteria “can multiply rapidly” in the “Danger Zone” between 40°F and 140°F. Its general rule for perishable food is never to leave it out for more than 2 hours — or 1 hour above 90°F. A jar of tea on a hot porch spends its entire brewing time inside that zone, and usually for far longer than an hour.

What does contamination look like? The Wikipedia summary of iced tea advises discarding tea that appears thick, syrupy, or has rope-like strands in it — and notes it may be hazardous even without those signs. That last part matters: you cannot reliably judge safety by looking.

Keep it in proportion: the Ohio State guidance acknowledges the statistical risk is not great. But the method skips the one step — real heat — that would kill whatever is in the water or on the leaves, then holds the tea where bacteria thrive. Since the refrigerator gives an equally smooth drink without that trade-off, there is little reason to take it.

If you still want to know how to make sun tea the traditional way, these steps reduce the risk. They do not eliminate it, and none of them makes sun tea as safe as refrigerator brewing.

1. Start with a scrupulously clean jar. Ohio State's guidance is to wash, rinse, and sanitize tea-making equipment regularly. Skip jars with spigots unless you can take the spigot apart and clean it; in 1996 Cincinnati health inspectors found high levels of coliform bacteria in the spigots of restaurant iced-tea dispensers that were not being cleaned daily.
2. Use cold, safe drinking water from a source you would happily drink untreated.
3. Add the tea — bags with the strings outside the lid make removal easy.
4. Keep the time in the sun as short as you can. Measured against the CDC's food-safety rule (no more than 1 hour above 90°F), a multi-hour steep in direct summer sun does not fit, which is why the shorter, the better.
5. Remove the tea and refrigerate immediately. The CDC advises keeping refrigerators at 40°F or below.
6. Make only what you will drink soon. Ohio State recommends brewing only enough tea that can be consumed within a few hours.
7. Discard anything thick, syrupy, or stringy without tasting it, and when in doubt, throw it out.

Notice how much of this routine is about getting the tea cold quickly. That is the real lesson.

Refrigerator tea — tea steeped in cold water in the fridge — is what Ohio State's guidance recommends instead of sun tea, and it is the method this site is built around. The Wikipedia summary of iced tea notes it has a dual advantage: it prevents the growth of harmful bacteria and the tea is already cold without adding ice. It gives you the same smooth, mellow pitcher with none of the guesswork.

1. Choose your tea. Black tea gives the classic sun-tea flavor; green, oolong, and herbal teas work too.
2. Measure. Follow the package if it has cold-brew directions — Lipton's Cold Brew family-size bags, for example, specify one bag per quart. Our cold brew tea ratio guide covers loose leaf and regular bags.
3. Combine with cold water in a clean pitcher or jar.
4. Refrigerate. Ohio State describes the steep as “six hours to overnight depending on how strong you like your tea.”
5. Remove the tea and serve over ice, with lemon or a little sweetener if you like.

That is genuinely all there is to it. If you want more detail on timing by tea type, see cold brew tea steep time; for a fuller walkthrough with troubleshooting, our step-by-step how to make cold brew tea guide is the place to start. And if you like the idea of tea bags in a jar, cold brew tea bags explains which bags work best.

If you came here asking how to make sun tea, this is the version we would hand you: the same jar, the same tea bags, just a colder shelf.

If you want iced tea today rather than tomorrow morning, the fastest safe route is to start hot. The Ohio State guidance, citing the Centers for Disease Control and the National Tea Association, recommends brewing tea bags at 195°F for three to five minutes, and notes that standard hot brewing is always hot enough to ensure undesirable microbes are killed.

The method:

• Brew a concentrated batch with hot water, using more tea than you would for a single mug, for three to five minutes.
• Remove the tea.
• Let it cool, then add cool water to bring the temperature down gradually before refrigerating or adding ice.

That gradual cooling is not only about speed. Ohio State explains that iced tea turns cloudy when tannins come out of solution because the tea is cooled too quickly. Adding cool water first, rather than dumping hot tea straight onto ice, helps keep it clear.

Hot-brewed iced tea tastes a little brisker than sun tea, because hot water pulls out more tannins. Our how to make iced tea guide covers the method in full.

Here is how the three methods compare, using only what the sources above state about temperatures, times, and safety:

	Sun tea	Refrigerator tea	Hot-brewed, then chilled
Brewing temperature	No hotter than about 130°F (Ohio State)	At or below 40°F, the CDC's fridge target	195°F recommended (Ohio State, citing CDC and the National Tea Association)
Brewing time	Hours in the sun	Six hours to overnight (Ohio State)	Three to five minutes, plus cooling
Where it sits during brewing	Inside the CDC's 40–140°F “Danger Zone”	Below it	Above it, then cooled
Kills microbes during brewing?	No (not hot enough)	No, but keeps them from multiplying	Yes, per Ohio State
Taste	Smooth, mellow	Smooth, mellow	Brisker; can cloud if chilled fast
Needs energy?	No	The fridge you already run	A kettle or stove

The refrigerator delivers sun tea's smooth taste while keeping the tea out of the danger zone for the whole steep. Hot brewing is the choice when speed matters.

Everything people love to add to sun tea works just as well in a fridge-brewed pitcher.

Teas that work well. Classic black tea bags give the familiar American iced-tea flavor; see cold brew black tea for options. Green tea turns sweet and soft when cold brewed, and our cold brew green tea recipe shows the shorter steep it prefers. Hibiscus and mint make caffeine-free pitchers.

Add-ins. Steep a few strips of lemon or orange peel, a handful of fresh mint, or sliced peaches with the tea. Wash fruit and herbs first, and keep the pitcher refrigerated.

Sweetening. Sugar dissolves poorly in cold tea, so make a simple syrup by dissolving sugar in an equal amount of hot water, cool it, and stir it in to taste. Honey can be handled the same way.

Serving. Pour over ice with a lemon wheel or a sprig of mint, or freeze some tea into cubes so the glass does not get watery.

For more pitcher ideas, our iced tea guide collects classic styles. Whatever you choose, the smooth taste comes from slow, gentle extraction — and the refrigerator does that safely.