Cold Brewing Tea

Cold brewed tea is the most overlooked technique in British tea drinking, and one of the highest quality small upgrades available for summer drinking. Made by steeping tea leaves in cold water for several hours rather than brewing in hot water, cold brewed tea produces dramatically different cups: smoother, less astringent, naturally sweeter, with reduced bitterness and a clean refreshing finish. With small adjustments, cold brewing suits almost every tea family and gives summer iced drinks that really do beat the hot then iced method most British drinkers fall back on. In one line: it works with almost any tea, it transforms green tea, and it is the secret to good iced tea at home.

This guide covers everything about cold brewed tea: the brewing chemistry that makes cold brewing different, the family by family approach for different tea types, the equipment, the storage, and how to use cold brewing across the British year.

The cold brewing chemistry

Cold brewing produces different cups than hot brewing because different tea compounds extract at different rates and temperatures. The key chemical points:

• Caffeine extracts more slowly at low temperatures but still extracts substantially given enough time; cold brewed tea has 60 to 80 percent of the caffeine of hot brewed tea after 6 to 12 hours. In figures: hot brewed Yorkshire Tea is about 50mg per 200ml against 30 to 40mg cold brewed at 12 hours, and hot brewed green tea about 30 to 40mg per 200ml against 20 to 30mg cold brewed at 8 hours
• Tannins extract slowly at cold temperatures: this is the key chemistry; tannins (responsible for astringency and bitterness) require heat for efficient extraction. Cold brewed tea has dramatically lower tannin content than hot brewed, commonly put at a 60 to 80 percent reduction against the same tea brewed hot
• Catechins in green tea may be better preserved: some research suggests cold brewing gives higher catechin retention than hot brewing; the difference either way is modest
• Amino acids and sugars extract well at cold temperatures: the L theanine and natural sweetness compounds that give tea its pleasant character extract efficiently in cold water
• Volatile aroma compounds extract differently: cold brewing produces different aromatic profiles than hot brewing; some teas show character in cold brewing that doesn't show in hot brewing

The practical effect: cold brewed tea is naturally smoother, less bitter, with most of the caffeine and pleasant flavour but dramatically less astringency. For drinkers who find hot brewed tea sometimes "too tannic" or "too bitter", cold brewing produces cups that emphasise the pleasant character without the bitter edge.

The basic cold brew method

The standard cold brewing approach:

1. Use 1 litre of cold filtered water
2. Add 4 to 6 tea bags (or 4 to 6 teaspoons of loose leaf tea) per litre; cold brewing typically uses slightly more leaf than hot brewing
3. Combine in a large jug or jar: ideally glass with a lid
4. Refrigerate for 6 to 12 hours; overnight is the typical approach. Some teas can be cold brewed for 4 hours; some benefit from 16+ hours for fuller character
5. Strain the leaves out before serving, removing tea bags or pouring through a fine mesh strainer
6. Serve over ice with optional lemon, fresh herbs, or sweetener
7. Store the prepared cold brew in the fridge, covered, and drink it soon

That's the entire technique. No specialist equipment beyond a jug or jar is needed; no temperature control; no precise brewing time; no monitoring required. Cold brewing is the easiest tea brewing technique once you know the principles.

Family by family cold brewing

Different tea families respond differently to cold brewing:

Black tea cold brewing, works well with the right leaf. Loose leaf and whole leaf blacks (English Breakfast, Assam, Ceylon, Darjeeling) give smooth, less bitter cups, and the reduced tannin extraction makes them dramatically smoother than the hot brewed then iced version. Fast extraction CTC bags are the weak case: Yorkshire Original and Tetley Original are built for a fast hot brew and come out thin and flat cold. They still earn their place in an iced milk tea, where the milk carries the cup, but for a black cold brew drunk neat use loose leaf. Use 6 bags per litre of water, 8 to 12 hour brewing time. The cup can be served neat with lemon or with milk for an iced milk tea.

Green tea cold brewing, this is where cold brewing really shines. Hot brewed green tea is often slightly bitter or astringent; cold brewed green tea reveals the sweet vegetal character without bitterness. Sencha, dragonwell, and similar high quality green teas are excellent cold brewed. Use 4 tea bags per litre, 6 to 8 hour brewing time. The result is dramatically smoother than any hot brewed green tea. Sencha, Long Jing (dragonwell), Bi Luo Chun and Pukka Three Mint are the ones worth starting with. See the sencha overview, the dragonwell overview and the best green teas list.

White tea cold brewing, excellent for delicate white teas. The gentle character of Silver Needle and white peony (Bai Mudan) shows particularly well in cold brewing; both are subtle and floral cold, and the natural sweetness emerges without any bitterness. 4 tea bags per litre, 8 to 12 hour brewing time. See the silver needle overview.

Oolong cold brewing, works well, particularly for lighter oolongs like tieguanyin. The complex floral character of light oolong shows excellently in cold brewing. 5 tea bags per litre, 8 to 10 hour brewing time. See the tieguanyin overview.

Pu erh cold brewing, the one family we would skip. The earthy compounds that make pu erh what it is need heat to develop, and cold brewed pu erh tends to taste muddy rather than interesting. Drink it hot. See the pu erh overview.

Herbal infusions, varies by herb. Most herbal teas work in cold brewing but produce different character than hot brewed versions:

• Hibiscus: excellent cold brewed; one of the best summer iced drinks
• Peppermint: excellent cold brewed; the menthol cooling sensation compounds with cold
• Chamomile: decent cold brewed; less aromatic than hot but pleasant
• Rooibos: excellent cold brewed; its natural sweetness and red colour suit iced drinks beautifully
• Berry and fruit blends: excellent cold brewed; the fruit character is highlighted. Pukka Berry Beautiful, Twinings Strawberry & Mango and Teapigs Super Fruit are the ones to try
• Ginger: milder than hot brewing; useful for those who find hot ginger tea too intense

For more on specific herbs see the hibiscus overview, peppermint overview, and rooibos overview.

Earl Grey and other flavoured blacks, cold brewed Earl Grey is a different drink from the hot version: the bergamot oil survives intact while the black base softens. Good with a slice of fresh lemon.

Teas that don't cold brew well

Cold brewing is forgiving, but it is not universal. These are the ones to leave hot:

• CTC tea bags (Yorkshire Original, Tetley Original). Designed for fast hot extraction. Cold brewed Yorkshire is thin and flat. Use them for what they are for, iced milk tea included, where the milk covers the gap.
• Pu erh. The earthy compounds need heat to develop. Cold brewed pu erh tastes muddy.
• Heavily roasted oolongs. The roast notes need heat to express.
• Lapsang Souchong. The smoke flavour is muted in cold brew.
• Matcha. A different category, you drink the whole leaf rather than infuse it. For a cold version, whisk it with cool water for iced matcha instead.

The British year for cold brewing

Cold brewing is sometimes seen as purely a summer technique, but it works across the year:

• Summer: the obvious season; cold brewed iced tea as alternative to soft drinks
• Autumn: useful for desk side drinking when central heating makes offices warm
• Winter: less common but works for evening drinking when you don't want hot caffeine; cold brewed decaf or herbal can replace evening hot tea
• Spring: the natural starting point for the cold brewing year as weather warms

For year round cold brew drinkers, keeping a 1-litre jug of cold brewed tea in the fridge becomes a daily habit; pour a glass when you want a cold drink, top up the jug when it gets low.

Equipment options

Cold brewing requires almost no specialist equipment:

Minimum equipment:

• A glass or plastic jug or jar with a lid (1 to 2 litre capacity)
• Tea bags or loose leaf tea
• Cold filtered water
• A fine mesh strainer (if using loose leaf)

Optional dedicated cold brew equipment:

• Glass cold brew bottles with built in infusers (£10 to £25), bottles designed specifically for cold brewing with internal mesh tubes; Hario and Bodum both make them, convenient but not necessary
• Tea pitcher with built in strainer makes pouring without separate straining easier
• Glass French press: doubles as cold brew vessel; the plunger handles straining
• Mason jars: simple and effective for batch cold brewing

For drinkers wanting to try cold brewing, starting with a basic glass jug from the kitchen cupboard is fine; specialist equipment is unnecessary unless you become a regular cold brew drinker.

The "supercharged" cold brew technique

One advanced technique worth knowing: combining cold brewing with brief hot brewing for fuller character:

1. Place tea leaves in cold water
2. Cold brew in the fridge for 6 to 8 hours as normal
3. After cold brewing, warm a small portion (about 100ml) of the cold brew in a small saucepan to just below simmering
4. Pour the warmed concentrated liquid back into the cold brew
5. This briefly extracts additional aromatic compounds without the tannin bitterness of full hot brewing
6. Strain and serve over ice

The resulting cup combines the smoothness of cold brewing with slightly more aromatic character than pure cold brewing produces. For drinkers who find pure cold brew slightly under flavoured, this technique provides a middle ground.

Storage and shelf life

Cold brewed tea storage considerations:

• Refrigerated storage: essential; cold brewed tea must be kept cold to prevent bacterial growth
• Drink it soon: we don't give a keeping time for home-made iced tea; make small batches and keep them covered in the fridge
• Sealed container keeps the tea from absorbing fridge odours
• Don't reuse leaves: the cold brewed leaves don't produce good second batches
• Don't freeze it: the texture suffers

Make small batches often rather than one big batch to keep: that way the jug in the fridge is always fresh.

Cold brew variations

Once you have basic cold brew working, several variations expand the technique:

Fruit infused cold brew add slices of fruit (peach, lemon, orange, berries) to the brewing water alongside the tea; the fruit infuses during the cold brewing for fruit tea like character.

Herbal mix cold brew combine multiple compatible herbal teas (peppermint and lemon balm, hibiscus and rosehip, chamomile and lavender) for complex herbal cold brews.

Iced milk tea cold brewed black tea served with cold milk over ice; smoother than hot brewed then iced milk tea, and the one preparation where a CTC bag still earns its place. The Indian "thanda chai", cold chai, is the same idea with chai spices: no heating needed, and cold brewing appears to keep more of the spice aroma than heating and then cooling does.

Cold brewed matcha whisk matcha with cold water and ice rather than the traditional hot preparation; produces a refreshing summer matcha drink. See the matcha overview.

Cold brew cocktail bases cold brewed tea provides excellent low tannin cocktail mixers; particularly good for tea based mocktails and modern tea cocktail recipes.

Sparkling cold brew top the finished cold brew up with sparkling water; fruit infused and hibiscus cold brews are the best of these. A lemon and ginger cold brew, sparkling, is a decent non alcoholic stand in for a gin and tonic.

Sun tea the same idea using sunlight instead of the fridge: tea and cold water in a clear glass jar on a windowsill or in the garden for 4 to 6 hours, slightly warm at the end. An older Southern US tradition. There is a theoretical concern about bacterial growth at warmer than fridge temperatures over long periods, so refrigerator cold brew is safer.

Flash chilled cold brew hot brew the tea as normal, then pour it straight over ice to cool it rapidly. A compromise that keeps some of cold brew's character and takes 5 minutes.

Iced tea, the double strength way brew hot at double strength and pour over ice; the melting ice brings it to drinking strength. Faster than cold brewing and slightly more bitter, and it is the American sweet tea approach.

Cold brewed iced latte cold brewed strong tea topped with cold milk over ice; iced chai latte and iced jasmine latte work particularly well this way.

What we stock for cold brewing

Browse the full black tea range, green tea range, herbal tea range, and fruit tea range for cold brew options. The most bought cold brew suitable teas on teas.co.uk:

• Teapigs Chocolate and Mint, 15 Tea Bags 37.5g
• True English Tea (T.E.T) Everyday English No 1, 20 Tea Bags 40g
• Typhoo QT One Cup Instant Tea With Whitener, 125g
• Twinings Bioblends Lemon, Ginger and Turmeric, 18 Tea Bags 40g
• True English Tea (T.E.T) Everyday Green Tea, 20 Tea Bags 35g
• Hyson Peach Infused Black Tea, 32 Tea Bags 32g

For comparisons across the wider tea landscape, see also: Twinings, Teapigs, Yorkshire Tea, Clipper, Pukka.

If you want the shopping shortlist: English Breakfast, Earl Grey, green tea, loose leaf tea, Darjeeling, oolong, and herbal tea. Shop the tea range at teas.co.uk for cold brewing; spend over £35 and UK delivery is free.

Cold brew tea, common questions

Is cold brew tea healthier than hot? Some evidence points that way: higher catechin retention in green tea, and lower tannin extraction means less iron binding. The differences are modest either way.

Can I cold brew any tea? Most teas, yes. CTC tea bags, pu erh and heavily roasted oolongs are the exceptions.

How long does cold brew take? 6 to 12 hours depending on the tea. Overnight is the practical answer for most.

Does cold brew have less caffeine? It has 60 to 80 percent of the hot brewed figure. Slightly gentler, not caffeine free.

Best tea for cold brew? Green tea, which is the transformation people notice first; hibiscus and fruit infusions for a bright glass; mint and herbal blends for clean refreshment.

The verdict on cold brewing

Cold brewed tea is one of the highest quality small upgrades available to British tea drinkers, and it's dramatically underused. The technique requires no equipment beyond a kitchen jug, no precision in temperature or timing, no specialist knowledge; just patience overnight in the fridge.

Next to hot brewed then iced tea, the difference in a cold brewed cup is large. Cold brewed tea is smoother, less bitter, naturally sweeter, and more refreshing. For summer iced tea drinking, cold brewing produces results that simply can't be matched by the hot brewing then cooling approach most British drinkers default to.

For drinkers who occasionally drink iced tea but find it slightly disappointing, switching to cold brewing transforms the experience. For drinkers who don't currently drink iced tea, cold brewing provides accessible introduction to summer tea drinking that's a meaningful upgrade over commercial iced tea or soft drinks.

The technique works particularly well for drinkers who specifically dislike astringency in hot tea; cold brewing minimises tannin extraction and produces dramatically smoother cups. For drinkers prone to digestive sensitivity from tannins, cold brewing provides a more tolerable approach while preserving the caffeine and pleasant character.

Don't reserve cold brewing only for summer; the technique works year round and provides useful evening alternatives to hot tea when you don't want hot caffeine before bed. A jug of cold brewed decaf or rooibos in the fridge becomes a useful daily habit across all seasons.

For the wider context see the loose leaf brewing guide, the water temperatures guide, the ultimate caffeine guide, the iced tea guide, the best tea for energy guide, the hibiscus overview, the peppermint overview, and the rooibos overview.

Family by family cold brewing, at a glance

The plain mechanism is the whole point: cold water extracts the pleasant, water soluble flavour and sweetness compounds efficiently but pulls the harsh tannins and the bitter catechins far more slowly, so a long fridge steep gives a cup that is smooth, naturally sweet and almost impossible to over brew. That is why cold brew flatters delicate green and white teas that scald easily when hot, and why a full bodied black turns mellow rather than astringent. Use roughly the same leaf as for a hot cup, or a little more, in cold water in the fridge, leave it for the times above, strain, and keep it sealed; we don't give a keeping time for home-made iced tea, so make small batches and drink them soon. It needs no special kit, a jug and a strainer are enough, though a dedicated bottle is tidier, and it is the single most forgiving brewing method there is because time, not temperature precision, does the work.

Curator's note: my summer fridge always has a 1-litre jar of cold brewed Pukka Three Mint or sencha. Pour over ice with a lemon wedge, done. Cheaper than soft drinks, better tasting, and the kids drink it without complaint. Lee, teas.co.uk, Tunbridge Wells.

Related on the wiki: Tea For Cold Weather The Winter Warming Guide.

More related guides

• Afternoon Tea, Start to Finish
• What Makes Tea Strong

More from the tea wiki

• Tea Storage by Tea Family
• Steeping Times by Tea Type
• Cold Brew Tea: Smooth Iced Tea, Never Bitter
• Pu-Erh: The Yunnan Fermented Tea Family
• Teapots and Infusers

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