| Nominativ | quartusdecimum, quartusdecima, quartusdecimus | quartusdecimae, quartusdecimi, quartusdecima |
| Genitiv | quartusdecimi, quartusdecimi, quartusdecimae | quartusdecimorum, quartusdecimorum, quartusdecimarum |
| Dativ | quartusdecimo, quartusdecimo, quartusdecimae | quartusdecimis |
| Akkusativ | quartusdecimam, quartusdecimum, quartusdecimum | quartusdecimos, quartusdecimas, quartusdecima |
| Ablativ | quartusdecimo, quartusdecima, quartusdecimo | quartusdecimis |
| Vokativ | quartusdecime, quartusdecimum, quartusdecima | quartusdecimae, quartusdecimi, quartusdecima |
