A typical 8 oz cup of brewed black tea contains approximately 45–70 mg of caffeine — about half the amount in a comparable cup of drip coffee, and roughly 1.5–2× the amount in green tea. Strong Assam or English Breakfast blends can reach the higher end of this range.
Black Tea Caffeine by Variety
All black teas come from Camellia sinensis fully oxidized leaves, but caffeine varies significantly by the origin of the leaves, the flush (harvest season), and brewing parameters.
| Variety / Product | Serving | Caffeine (approx.) | Level |
|---|---|---|---|
| Generic Black Tea (bagged) | 8 oz, 3 min steep | ~45–55 mg | Low-Moderate |
| English Breakfast | 8 oz, 3–5 min steep | ~45–70 mg | Moderate |
| Assam (CTC or loose leaf) | 8 oz, 3–5 min steep | ~55–70 mg | Moderate |
| Darjeeling (first flush) | 8 oz, 3 min steep | ~45–60 mg | Low-Moderate |
| Earl Grey | 8 oz, 3 min steep | ~40–60 mg | Low-Moderate |
| Chai Tea Latte (café, 12 oz) | 12 oz | ~50–70 mg | Moderate |
| Starbucks Chai Latte (Grande) | 16 oz | ~95 mg | Moderate |
| Iced Black Tea (bottled, 16 oz) | 16 oz | ~50–90 mg | Moderate |
| Lipton Black Tea (bag) | 8 oz, 2 min | ~40–50 mg | Low-Moderate |
| Yorkshire Tea (bag) | 8 oz, 4 min | ~50–65 mg | Moderate |
| PG Tips (bag) | 8 oz, 3 min | ~45–55 mg | Low-Moderate |
Why Black Tea Caffeine Varies
Black tea's caffeine is highly responsive to how you prepare it:
- Steep time: Extending steep from 1 minute to 5 minutes can double the caffeine extracted. A "strong" cuppa brewed UK-style (4–5 minutes with boiling water) delivers considerably more caffeine than a short steep.
- Water temperature: Black tea is typically brewed at 95–100°C (203–212°F). Higher temperature maximizes caffeine extraction from the leaves.
- Leaf grade: CTC (cut-tear-curl) teas used in most teabags release caffeine faster and at higher concentrations than whole-leaf teas, because they have more surface area. A 3-minute steep of a CTC bag extracts more caffeine than the same time with large loose-leaf pieces.
- Leaf origin: Assam teas are known for high caffeine content (and the strong, malty flavor that comes with it). Darjeeling is typically lower. Chinese black teas like Yunnan or Keemun fall somewhere in the middle.
- Amount of tea used: More grams of tea per volume of water = more caffeine. UK-style tea is often brewed with 2.5–3 g per cup; some specialty teas use more.
Black Tea vs. Coffee vs. Other Drinks
| Drink (8 oz unless noted) | Caffeine (approx.) |
|---|---|
| Drip Coffee | ~95–120 mg |
| Black Tea (brewed) | ~45–70 mg |
| Matcha (1 tsp) | ~60–80 mg |
| Espresso (1 oz shot) | ~63–75 mg |
| Green Tea (brewed) | ~20–45 mg |
| Decaf Coffee | ~2–15 mg |
Black tea sits in an interesting position: it delivers roughly the same caffeine as a single espresso shot, but spread over a much larger volume (8 oz vs. 1 oz). This generally produces a gentler, slower caffeine absorption than espresso.
Compared to drip coffee, black tea delivers about 50–70% less caffeine per cup — a significant enough difference that regular tea drinkers often notice reduced stimulation when they accidentally switch to coffee. For a full drink-to-drink comparison, use the Caffeine Comparison tool.
How Black Tea Compares to Green Tea and Matcha
All three come from the same plant. The key differences:
- Processing: Black tea is fully oxidized; green tea is unoxidized; matcha is shade-grown and ground whole.
- Caffeine per cup: Black tea (~45–70 mg) generally delivers more than green tea (~20–45 mg), while matcha (~60–80 mg) often exceeds both despite being "green" because you consume the whole leaf.
- L-theanine: All three contain L-theanine, but matcha has the highest concentration due to shade-growing.
If you're reducing caffeine by switching from coffee to tea, green tea is a bigger step down than black tea. See our green tea guide and matcha guide for detailed comparisons.
Black Tea and Sleep: Timing Guidelines
Black tea at 45–70 mg per cup follows the same caffeine metabolism rules as any other caffeinated drink. With a typical 5-hour half-life:
- One cup (60 mg) at 6 PM → ~30 mg at 11 PM. Probably fine for most people.
- Two strong cups (130 mg total) at 7 PM → ~65 mg at midnight. More likely to affect sleep quality.
- English Breakfast with milk at 3–4 PM → generally safe for a 10–11 PM bedtime by the 8-hour rule.
The Caffeine Half-Life Calculator lets you enter any caffeine amount and see your exact decay curve. For a quick bedtime answer, try the Coffee Cutoff Time tool.
Keep the FDA's guideline in mind: 400 mg/day for healthy adults, 200 mg/day during pregnancy. Six to eight cups of black tea per day would approach the adult limit — more than most people drink — but chai lattes and strong breakfast teas can add up faster than expected.
Black tea is the most consumed tea worldwide, and many people drink it throughout the day without tracking their caffeine. If you have three or four strong cups plus an afternoon espresso, your total may be higher than you think. Unbuzz lets you log any tea and see your daily cumulative caffeine in real time.
