| Singular | Plural | |
|---|---|---|
| Nominativ | phantasia | phantasiae |
| Genitiv | phantasiae, phantasiai | phantasium, phantasiarum |
| Dativ | phantasiae, phantasiai | phantasiabus, phantasiis |
| Akkusativ | phantasiam | phantasias |
| Ablativ | phantasia, phantasiad | phantasiis, phantasiabus |
| Vokativ | phantasia | phantasiae |