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US-05 and S-04 are the two most widely used dry ale yeasts in homebrewing, both from Fermentis, both reliable and consistent, and both producing distinctly different results that make the choice between them genuinely consequential for recipe character. I’ve fermented the same American pale ale wort split between US-05 and S-04 to isolate the yeast contribution, and the differences are more pronounced than many homebrewers expect from two “clean” dry yeasts.
US-05 vs. S-04: key specifications compared
Fermentis Safale US-05: American Ale yeast. The same or closely related strain to the Chico yeast used by Sierra Nevada Brewery, White Labs WLP001 and Wyeast 1056 are liquid equivalents. Attenuation: 73–77% (high, produces a dry, crisp finish). Flocculation: medium-high. Alcohol tolerance: up to 11% ABV. Recommended temperature range: 15–24°C (59–75°F), optimal 18–21°C. Flavor profile: very clean, minimal ester contribution, allows hop and malt character to express clearly. At 18–19°C, US-05 produces essentially no detectable ester character, it is the most neutral American ale dry yeast widely available. Very slight apple/green apple character (acetaldehyde) if underpitched or fermentation is rushed; this is usually eliminated with a 48-hour diacetyl rest at 20°C before packaging. Produces brilliant clarity with cold crashing; settles tightly and compactly. Fermentis Safale S-04: English Ale yeast. Widely considered a close equivalent to the Whitbread yeast used in classic British commercial brewing. Attenuation: 71–75% (slightly lower than US-05, marginally sweeter finish). Flocculation: high (very compact settling, S-04 drops out of suspension faster than any other common dry yeast). Alcohol tolerance: up to 9% ABV. Recommended temperature range: 15–22°C (59–72°F), optimal 18–20°C. Flavor profile: light fruity esters (stone fruit, apple, slight peach), slight yeasty-bready note at lower temperatures, clean at optimal temperature. At 18–20°C, S-04 produces a subtle but detectable fruity-ester character that adds complexity to English ales and American ales where fruit character is compatible. At warmer temperatures (22°C+), ester production increases significantly, can produce banana or fusel notes above 23°C.
When to choose US-05 vs. S-04
Use US-05 when: the recipe is hop-forward and you want maximum hop character expression without yeast ester competition, American pale ales, West Coast IPAs, NEIPAs, American lagers fermented warm, and any style where the finished beer should read as “clean” with no yeast-derived fruit. US-05 is also the right choice when you’re troubleshooting a recipe and want to isolate whether flavor issues come from ingredients or process, its clean fermentation profile removes yeast as a variable. Best styles: American IPA, American pale ale, West Coast DIPA, cream ale, American wheat, American lager (warm fermentation). Use S-04 when: the recipe benefits from slight fruity-ester complexity alongside hop or malt character, English ales, American amber ales, best bitters, English stouts, and any style where a subtle yeast contribution adds depth. S-04’s slight fruity character also complements certain hop varieties: the stone fruit ester note pairs well with Centennial’s orange-citrus and Amarillo’s tangerine, creating a slightly more complex result than US-05 in the same recipe. S-04’s very high flocculation makes it excellent for beers where fast, clear fermentation is needed, it drops bright faster than US-05 without fining. Best styles: English bitter, ESB, robust porter, English IPA, American amber ale, session ale. Temperature note: Both yeasts benefit from starting fermentation at the lower end of the range (17–18°C) to limit ester production, then allowing temperature to rise slightly (to 20°C) as fermentation winds down to ensure complete attenuation. Pitching both at 22°C+ risks excessive ester production and potential off-character development.
Common Questions
Can I substitute S-04 for US-05 in a standard IPA recipe?
Yes, S-04 in an American IPA recipe produces a good beer, but a perceptibly different one. The slight fruity-ester contribution of S-04 adds complexity to the hop character in a way that some homebrewers prefer and others find less clean than US-05. S-04’s slightly lower attenuation means the finished beer will have 1–2 gravity points more residual sweetness than US-05 in the same recipe, which affects both perceived body and the balance between hop bitterness and malt sweetness. For a hop-forward American IPA where bitterness balance is precise: the lower attenuation of S-04 can shift the hop-malt balance toward malt, making the beer slightly less bitter in practice than the IBU calculation suggests. For a session IPA or lower-IBU pale ale where the slight malt sweetness from S-04’s lower attenuation is welcome: the substitution works well and the ester character adds approachability. For a West Coast DIPA at 75+ IBU: the fruity-ester contribution of S-04 can become confusing at high bitterness levels, US-05’s clean fermentation profile is preferable. Direct substitution without adjustment works fine for most recipes; if you’re precision-brewing and care about exact gravity points, add 0.25–0.5 lb less crystal malt when using S-04 to compensate for its slightly lower attenuation.
