Cold Brew Tea: How to Make It at Home With a Cold Brew Maker
Cold brew tea is the simplest iced tea you'll ever make — and the best-tasting one. No heat. No bitterness. No watching a kettle. Just tea leaves, cold water, and a few hours in the fridge.
If your iced tea ever comes out bitter or astringent, cold brewing is what fixes it. Cold water extracts differently from hot water — it pulls the smooth, naturally sweet compounds from tea leaves while leaving behind the harsh tannins that hot steeping releases in the first 30 seconds.
This guide covers ratios, steep times by tea type, the best teas for cold brewing, flavor combinations, and how to make cold brew tea using the Ovalware Cold Brew Maker — a vessel most people already have for coffee, but that works beautifully for tea too.
What Is Cold Brew Tea?
Cold brew tea is made by steeping tea leaves or bags in cold or room-temperature water for 2 to 12 hours, with no heat at any point. The slow, cold extraction draws out a different chemical profile than hot steeping — resulting in a smoother, naturally sweeter, less bitter cup that rarely needs added sugar.
According to Sweet Steep's cold brew iced tea guide, cold brewing produces noticeably smoother results because the sharp tannins and bitter compounds that release rapidly in hot water stay behind during cold extraction. The result is iced tea that tastes clean and pleasant without sweetener — rare for traditionally brewed iced tea.
Cold brew tea has roots in Japan, where it's called mizudashi (水出し) — literally "water extraction." Green tea is the most common variety in Japanese tradition, but the method works across black tea, white tea, oolong, herbal blends, and rooibos.
Cold Brew Tea vs Hot Brewed Iced Tea: What's Different?
Cold brew and hot brewed tea are chemically different drinks made from the same leaves. Hot water extracts more total compounds — including both desirable flavors and the harsh tannins that create bitterness. Cold water extracts fewer compounds but a better balance, pulling sweetness and delicacy while leaving bitterness behind.
| Factor | Hot Brew Iced Tea | Cold Brew Tea |
|---|---|---|
| Bitterness | Higher — tannins extract quickly in heat | Lower — tannins stay behind |
| Sweetness | Needs sugar to balance bitterness | Naturally sweeter — less sugar needed |
| Caffeine | Full extraction | 30–50% less than hot brew |
| Active prep time | 15–30 minutes | 2–5 minutes (then hands-off) |
| Total time | 30–60 minutes with cooling | 4–12 hours (mostly fridge time) |
| Best for | When you need it immediately | Better flavor, prepped the night before |
Research published in PMC on rooibos cold brew vs. hot brew found that cold and hot extraction produce different antioxidant profiles — neither method is universally superior, but cold brew retains certain compounds that degrade in heat. ScienceInsights notes that cold-brewed green tea can produce higher total antioxidant activity despite extracting fewer overall compounds, because some beneficial catechins extract efficiently in cold water.
Cold extraction also extracts 30–50% less caffeine than hot water, according to research cited by Your Tea HQ. If you're reducing caffeine intake, cold brew tea is a practical way to enjoy the ritual without the stimulant load.
Cold Brew Tea Ratios and Steep Times by Tea Type
The standard cold brew tea ratio is 10–15 grams of loose leaf tea (or 1–2 tea bags) per 1 liter of cold water. Lighter teas need less leaf and less time; heartier teas need more of both.
| Tea Type | Amount per 1L | Steep Time (fridge) | Flavor Notes |
|---|---|---|---|
| Green tea (sencha, gyokuro) | 10–12g loose leaf | 4–8 hours | Delicate, sweet, grassy, umami |
| White tea | 10–12g loose leaf | 6–8 hours | Floral, very light, subtle |
| Oolong | 12–15g loose leaf | 6–10 hours | Complex, fruity, lightly floral |
| Black tea (Assam, Ceylon) | 12–15g loose leaf | 8–12 hours | Rich, malty, bold |
| Herbal / chamomile | 10–15g | 6–10 hours | Honey-sweet, gentle, varies by blend |
| Rooibos | 12–15g | 8–12 hours | Naturally sweet, woody, caffeine-free |
According to Cold Brew Ratio Calculator's cold brew tea guide, 12–15 grams of loose leaf per liter gives enough body without feeling overwhelming. For delicate teas like green and white, 1–1.5g per 100ml is appropriate; for black tea and oolong, 1.5–2g per 100ml works better.
Brew Buch recommends starting at the lower end of steep times and tasting as you go. Unlike hot steeped tea, which can become unpleasantly bitter if you overshoot by even a minute, cold brew tea is forgiving — an extra hour rarely ruins it.
How to Make Cold Brew Tea With Your Cold Brew Maker
The Ovalware Cold Brew Maker was designed for coffee — but its borosilicate glass carafe and fine-mesh stainless steel filter make it genuinely well-suited for tea. The filter catches loose leaf tea reliably, the glass carafe lets you see exactly how deep the color is getting, and the sealed lid keeps other fridge smells out during the long steep.
What You Need
- Loose leaf tea or tea bags
- Cold, filtered water
- Ovalware Cold Brew Maker (1.0L or 1.5L)
Method
- Add tea to the filter. If using loose leaf tea, add your measured amount directly to the stainless steel filter. If using tea bags, place them inside the filter or hang them over the rim of the carafe directly into the water.
- Fill with cold water. Pour cold, filtered water into the carafe over the filter. Give it a gentle stir to make sure the tea is fully submerged.
- Seal and refrigerate. Place the lid on the carafe and put it in the fridge.
- Steep for the appropriate time. Use the table above as your guide. Green teas: 4–8 hours. Black teas and rooibos: 8–12 hours. When in doubt, taste at the lower end and steep longer if you want more strength.
- Remove the filter and serve. Pull out the stainless steel filter with the leaves. Pour your cold brew tea over ice or straight from the carafe. Ready to drink — no dilution needed.
A note on tea bags: bags typically contain smaller, finely cut tea that can occasionally pass through the stainless steel filter mesh. If you see tiny particles in your brew, switch to loose leaf for cleaner results. Jeeves & Jericho and Fraser Tea both recommend loose leaf for cold brew for this reason — the larger leaf size stays in the filter cleanly.
Best Teas for Cold Brewing
Some teas cold brew exceptionally well. Others are better hot. Here's where to start:
- Japanese green teas (sencha, gyokuro, hojicha). Cold brewing is the traditional Japanese method for these teas — it's how they're meant to be made. Cold water brings out umami sweetness that hot water destroys. Your Tea HQ notes that cold-brewed green tea extracts catechins like EGC particularly efficiently in cold water. Gyokuro cold brew is a revelation.
- White tea. The most forgiving tea to cold brew — almost impossible to over-extract. Results are floral, delicate, and light. Perfect for hot summer days when you want something refreshing but subtle.
- Black tea (Assam, Ceylon, Darjeeling). Takes the longest to cold brew but produces a rich, malty result that holds up beautifully over ice with a squeeze of lemon. Darjeeling cold brew is especially floral.
- Rooibos. Naturally caffeine-free and naturally sweet. Cold brew rooibos is one of the most beginner-friendly options — hard to get wrong. US Two Tea notes that rooibos retains its antioxidant content well in cold extraction.
- Herbal blends. Chamomile, hibiscus, lemon verbena, peppermint — all cold brew beautifully. Hibiscus makes a vivid, tart cold brew that looks as striking as it tastes.
- Oolong. More complex than green tea, more delicate than black. Cold brewed oolong is layered, fruity, and naturally sweet — a great introduction to cold brew tea for anyone skeptical about the method. Cookie and Kate's cold brew iced tea guide highlights oolong as one of the best varieties for home cold brewing.
Cold Brew Tea Flavor Combinations Worth Trying
Cold brew tea is an excellent base for flavored drinks. The naturally clean, smooth flavor carries additions without muddiness. These combinations are worth making a batch for:
- Cold brew green tea + fresh mint + honey. Add a sprig of mint to the filter for the last 2 hours of steeping. Sweeten with a small amount of honey to taste. Fresh, bright, and genuinely refreshing.
- Cold brew black tea + lemon + ginger. Add a slice of fresh ginger and a strip of lemon peel to the filter when steeping. The cold extraction keeps ginger's heat mellow and aromatic rather than sharp.
- Cold brew hibiscus + cold brew green tea, equal parts. Pink, tart, sweet, and beautiful. No sugar needed. One of the most visually striking drinks you can make at home.
- Cold brew chamomile + vanilla. Add a split vanilla bean alongside chamomile leaves when steeping. Tastes like a gentle dessert — great for evenings.
- Cold brew oolong + fresh peach. Add fresh or frozen peach slices to the carafe for the final 4 hours of steeping. Peach sweetness mirrors oolong's natural stone-fruit notes perfectly.
If you enjoy cold-steeped summer drinks, our espresso tonic recipe and cold brew coffee cocktails guide use a similar prep-ahead approach.
Frequently Asked Questions About Cold Brew Tea
How long should you steep cold brew tea?
Steep time depends on the tea type. Green and white teas: 4–8 hours. Oolong and herbal teas: 6–10 hours. Black tea and rooibos: 8–12 hours. Cold brew tea is more forgiving than hot steeped tea — an extra hour rarely creates bitterness. Start at the lower end, taste, and steep longer if you want more strength.
Is cold brew tea healthier than regular iced tea?
Cold brew tea extracts 30–50% less caffeine than hot brewing, making it lower in stimulants — useful for people managing caffeine intake. It's naturally sweeter, so most people add less or no sugar compared to hot-brewed iced tea. Research on cold brew green tea found higher total antioxidant activity in some cold infusions despite lower overall compound extraction. Neither method is universally healthier; they produce different drinks from the same leaves.
Can I use the Ovalware Cold Brew Maker for tea?
Yes. The Ovalware Cold Brew Maker's stainless steel filter and borosilicate glass carafe work well for loose leaf tea. Add tea to the filter, fill with cold water, and steep in the fridge for 4–12 hours based on your tea type. Loose leaf tea gives cleaner results than bags, which sometimes release fine particles through the mesh filter. The carafe is dishwasher safe for easy cleanup.
What is the cold brew tea ratio?
The standard ratio is 10–15 grams of loose leaf tea per 1 liter of cold water. For green and white teas, use 10–12g per liter. For black tea and rooibos, use 12–15g per liter. If using tea bags, 1 bag per 240ml (8oz) of water is a reliable starting point. Adjust to your taste after the first batch.
Does cold brew tea have less caffeine?
Yes. Cold water extracts roughly 30–50% less caffeine from tea leaves than hot water does. Cold-brewed black tea contains approximately 20–40mg of caffeine per cup compared to 40–70mg when hot-brewed from the same leaves. Green tea and white tea cold brews are similarly reduced. Rooibos is naturally caffeine-free regardless of brewing method.
The Bottom Line
Cold brew tea sounds more involved than it is. Measure your tea, add cold water, put it in the fridge. Wake up to the best iced tea you've ever made at home.
If you already have an Ovalware Cold Brew Maker for your coffee, you have everything you need to start tonight. Same process, different leaves. And if you're cold brewing both coffee in the morning and tea in the afternoon — that's a summer routine worth building around.
New to cold brew entirely? Our cold brew vs iced coffee guide covers the basics, and our steep time guide for cold brew coffee explains the extraction principles that apply to tea too.
