| Oxbow Brewing Company | |
| Oy Sinebrychoff AB | Kerava, Finland |
| Oyster Bar Bistro and Brewery | Fort Wayne, Indiana |
| Ozark Beer Company | Rogers |
| Pabst Brewing Company | San Antonio, Texas |
| Pacific Beach Brewhouse | Pacific Beach, California |
| Pacific Coast Brewing | Oakland, California |
| Pacific Rim Brewing | Seattle, Washington |
| Paddock Wood | Saskatoon |
| Palm Breweries | Steenhuffel, Belgium |
| Palmetto Brewing | Charleston, South Carolina |
| Palo Alto Brewing Company | Mountain View, CA |
| Pang Pang Brewery | Stockholm, Sweden |
| PangPang Brewery | Stockholm, Sweden |
| Panhead Custom Ales | Upper Hutt |