| Oscuro Org | Commonwealth Brewing Co. | | |
| Oseka | The Garden Brewery | New England IPA | 6.2% |
| Osiris | 3rd Sign Brewery | American Imperial Stout | 9.0% |
| Osiris | Sun King Brewing Company | American Pale Ale | 5.6% |
| Osiris-Rex | Black Project Spontaneous & Wild Ales | | 9.0% |
| Oskar HMS Ark Royal | Noctem Artisans Brasseurs | New England IPA | 7.0% |
| Oskar KMS Bismarck | Noctem Artisans Brasseurs | American IPA | 7.0% |
| Oskar KMS Cossack | Noctem Artisans Brasseurs | New England IPA | 7.0% |
| Osmosis | Sapwood Cellars | Czech Amber Lager | 5.8% |
| Osmotar | Plan Bee Farm Brewery | Wild Ale | |
| Oso | Cismontane Brewing | English Porter | 10.0% |
| Oso Bueno | 11 Below Brewing | American Amber / Red Lager | 5.3% |
| Oso Furioso | Sudwerk Brewing | Doppelbock | 9.0% |
| Osprey's Fresh Catch | Horus Aged Ales | American IPA | 7.0% |
| Ossian | Inveralmond Brewery | English Pale Mild Ale | 4.1% |