Best L-Theanine Supplements 2026: Cost per Effective Dose
200 mg of L-theanine costs $0.020 to $0.76 across the 8 products below, at each brand’s own list price. Our pick, Momentous L-Theanine 200 mg, is $0.67 and is on NSF Certified for Sport and NSF/ANSI 173, lists that check what is in the bottle.
By Erin Rose Updated October 7, 2026 How we score
What 200 mg costs, brand by brand
Each product in the size the link opens, at the brand’s own list price, checked October 7, 2026. Prices at other stores may differ.
| Product and size | Per 200 mg |
|---|---|
| BulkSupplements L-Theanine Powder 250 g, list $24.97 · 200 mg in about 0.2 g of powder (you need a milligram scale) | $0.020 |
| Horbaach L-Theanine 400 mg per serving 120 capsules (60 servings), list $10.49 · 400 mg in 2 capsules | $0.087 |
| Nutricost Caffeine with L-Theanine 100 mg each 240 capsules, list $15.97 · 100 mg in 1 capsule | $0.13 |
| Sports Research L-Theanine 200 mg with Suntheanine 60 softgels, list $19.95 · 200 mg in 1 softgel | $0.33 |
| Nature Made Chewable L-Theanine 200 mg 50 count, list $16.99 · 200 mg in 1 chewable tablet | $0.34 |
| NOW L-Theanine 200 mg with Inositol 120 veg capsules, list $45.99 · 200 mg in 1 veg capsule | $0.38 |
| Momentous L-Theanine 200 mg 60 capsules, list $39.99 · 200 mg in 1 capsuleNSF Certified for Sport + NSF/ANSI 173 | $0.67 |
| Thorne Theanine 200 mg 90 capsules, list $68.00 · 200 mg in 1 capsuleNSF/ANSI 173 | $0.76 |
We priced 23 L-theanine products at every size each brand sells; these 8 are the best value of each kind. How many capsules make 200 mg: our dosage page.
Why we price 200 mg
200 mg is the dose trials used most. Labels differ: some give 200 mg in 1 capsule, some in 2. A “400 mg” bottle can mean 2 capsules of 200 mg. So we price 200 mg of L-theanine itself, not a capsule or a serving. Caffeine, GABA and green tea in a product do not count.
What trials of L-theanine measured: the research, read straight. How much to take: our dosage page.
5 L-theanine products we checked but did not price
- Pure Encapsulations L-Theanine (60 capsules): No list price we can cite: the brand sells through practitioners and we do not use Amazon prices. Its NIH label gives 200 mg of Suntheanine a capsule (400 mg in 2).
- Integrative Therapeutics L-Theanine (60 capsules): A practitioner brand: its page shows $22.00 next to 'Sign in' and 'How To Order', so we could not confirm a price a shopper can pay. Label: 200 mg in 2 capsules.
- Solgar L-Theanine 150 mg (60 veg capsules): We could not read Solgar's store, so we have no list price. Its NIH label gives 150 mg of Suntheanine a capsule.
- Natural Factors Suntheanine 200 mg chewable (60 tablets): We found no Natural Factors US store page to price it (only a retailer). The label is 200 mg in 2 chewable tablets (100 mg a tablet), Suntheanine, 3 g added sugar.
- Sports Research L-Theanine + Caffeine (60 softgels): We could not read the brand's store, so we have no list price. Its NIH label gives 200 mg AlphaWave L-theanine and 100 mg caffeine a softgel.
Sources
- Prices: each brand’s own list price, its regular one-time price, for every size it sells (sale, subscribe and multi-bottle prices left out), checked October 7, 2026. We quote no Amazon prices; Amazon is only where the buy links go.
- Labels: each brand’s page or the NIH Dietary Supplement Label Database. Testing: NSF/ANSI 173, NSF Certified for Sport, Informed Choice and Informed Sport, read October 7, 2026; USP Verified from our copy of September 22, 2026. Momentous is NSF Certified for Sport listing 1600891; Thorne Theanine is on NSF/ANSI 173 only.
The unit is 200 mg of L-theanine as the label states it. Scores updated October 7, 2026.