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