| masculin | feminin | neuter | plural | |
|---|---|---|---|---|
| Nominative | надбавочный | надбавочная | надбавочное | надбавочные |
| Genitive | надбавочного | надбавочной | надбавочного | надбавочных |
| Dative | надбавочному | надбавочной | надбавочному | надбавочным |
| Accusative inanimate | надбавочный | надбавочную | надбавочное | надбавочные |
| Accusative animate | надбавочного | надбавочную | надбавочное | надбавочных |
| Instrumental | надбавочным | надбавочной / надбавочною | надбавочным | надбавочными |
| Prepositional | надбавочном | надбавочной | надбавочном | надбавочных |
| Short form | надбавочен | надбавочна | надбавочно | надбавочны |