Does Cold Brew Tea Have More Caffeine?
There's a common belief that cold brew coffee has more caffeine — and people assume the same applies to tea. The reality is more nuanced, and for tea specifically, cold brewing almost always produces less caffeine than hot brewing.
The Short Answer: Cold Brew Tea Has Less Caffeine
Cold brewing typically extracts 25–40% less caffeine than hot brewing with the same amount of tea. Hot water is far more efficient at dissolving caffeine — it pulls everything out quickly. Cold water is gentler and slower, extracting less of the total caffeine available in the leaves.
Why Hot Water Extracts More Caffeine
Caffeine is water-soluble, but temperature dramatically affects extraction rate. At boiling temperature (212°F), caffeine dissolves almost immediately. At refrigerator temperature (~40°F), it dissolves very slowly over 8–12 hours — and never reaches the same total extraction as hot brewing.
This is actually one of the reasons cold brew tea tastes smoother: less caffeine extraction means less of the slightly bitter edge that caffeine contributes to flavor.
Cold Brew Caffeine Estimates by Tea Type
| Tea Type | Hot Brew (8oz) | Cold Brew (8oz, 12hr) |
|---|---|---|
| Black Tea | 40–70mg | 25–45mg |
| Green Tea | 25–45mg | 15–30mg |
| Rooibos | 0mg | 0mg |
| Chamomile | 0mg | 0mg |
| Yerba Mate | 60–90mg | 40–65mg |
Want Zero Caffeine? Go Herbal or Rooibos
If you're avoiding caffeine entirely, cold brewing herbal teas and rooibos is the perfect solution. Our Citrus Setter Rooibos, Chamomile Flowers, and Hibiscus are all completely caffeine-free and cold brew beautifully — bright, flavorful, and refreshing.
Want More Caffeine? Try This
If you specifically want the smooth taste of cold brew with higher caffeine, use a higher leaf-to-water ratio (1.5–2x the normal amount) and brew for the full 12 hours. You'll still have less caffeine than hot brew, but the gap narrows significantly.
Our Earl Greyhound black tea cold brewed at a higher ratio makes a bold, smooth iced tea that still delivers a meaningful caffeine kick.
Bottom Line
Cold brew tea = less caffeine, smoother flavor, no bitterness. If you're sensitive to caffeine or just want a gentler afternoon drink, cold brew is an excellent choice — especially with naturally caffeine-free options like rooibos and chamomile.
For a cold brew with no caffeine concerns at any hour, try our Citrus Setter Rooibos or Chamomile Flowers. Both are naturally caffeine-free and produce smooth, mellow cold brews.