| # | Name | Origin | Meaning | Gender | |
|---|---|---|---|---|---|
| 321 | Odin | Anglo-Saxon | Wealthy defender. | M | |
| 322 | Odon | Anglo-Saxon | Wealthy defender. | M | |
| 323 | Ody | Anglo-Saxon | Wealthy defender. | M | |
| 324 | Offa | Anglo-Saxon | Name of a king. | M | |
| 325 | Ord | Anglo-Saxon | Spear. | M | |
| 326 | Ordway | Anglo-Saxon | Warrior armed with a spear. | M | |
| 327 | Orlege | Anglo-Saxon | Battle strife. | M | |
| 328 | Ormod | Anglo-Saxon | Sad. | M | |
| 329 | Orvin | Anglo-Saxon | Brave friend. | M | |
| 330 | Orvyn | Anglo-Saxon | Brave friend. | M | |
| 331 | Osric | Anglo-Saxon | Divine ruler. | M | |
| 332 | Oswald | Anglo-Saxon | Name of a king. | M | |
| 333 | Oswine | Anglo-Saxon | Name of a king. | M | |
| 334 | Oswiu | Anglo-Saxon | Name of a king. | M | |
| 335 | Oswy | Anglo-Saxon | Name of a king. | M | |
| 336 | Oxa | Anglo-Saxon | Ox. | M | |
| 337 | Page | Anglo-Saxon | Page. | M | |
| 338 | Paige | Anglo-Saxon | Page. | M | |
| 339 | Peada | Anglo-Saxon | Name of a prince. | M | |
| 340 | Pearce | Anglo-Saxon | Rock. | M | |