| Brewery | Location |
|---|---|
| Otto's Pub and Brewery | State College, Pennsylvania |
| Oud Beersel Brewery | Belgium |
| Our Mutual Friend | |
| Ouster City Brewing Company | Apalachicola |
| Out of Bounds Brewing Company | Rocklin |
| Out.Haus Ales | Northwood |
| Outcast Brewing | Calgary |
| Outer Banks | |
| Outer Range Brewing Co. | Frisco |
| Outerbelt Brewing | Carroll, Ohio |
| Outland | Fontenay-sous-Bois, France |
| Outlaw Brewing | Bozeman, Montana |
| Overshores Brewing Co. | |
| Overtone Brewing Co | Glasgow , United Kingdom |
| Overworks |