| Brewery | Location |
|---|---|
| Oasis Brewery Annex | Boulder, Colorado |
| Oasis Texas Brewing Company | Austin |
| Oast House Brewers | Niagara-on-the-Lake, Canada |
| Obec Brewing | Seattle, Washington |
| Obercreek Brewing Company | Wappingers Falls |
| Obolon Brewery | Kiev, Ukraine |
| Ocean City Brewing Company | Ocean City |
| Oceanbryggeriet | Göteborg, Sweden |
| Oceanside Ale Works | Oceanside, California |
| Ocelot Brewing | Dulles, VA |
| Oconomowoc Brewing | Oconomowoc, Wisconsin |
| Octabrew | |
| Octant - Microbrasserie Inc. | Rimouski, Canada |
| Octopi Brewing | Waunakee, WI |
| Odd Breed Wild Ales | Pompano Beach |