Seleucid calendar is a lunisolar calendar that was used in ancient Macedon in the 1st millenium BC. It consisted in 12 lunar months (354 years per day), which needed intercalary months to stay in step with seasons. The seleucid calendar was based in the Babylonian calendar with the substitution of Macedonian names for the Babylonian ones. Finally an inscription from Kassandreia of about ca. 306-298 BC bearing a month Ἀθηναιῶν Athenaion suggests that some cities may have used their own months even after the 4th century BC Macedonian expansion.
- Δίος (Dios, moon of October)
- Ἀπελλαῖος (Apellaiios, moon of November, also a Dorian month - Apellaiōn was a Tenian month)
- Αὐδυναῖος or Αὐδναῖος (Audunaios or Audnaios, moon of December, Cretan month also)
- Περίτιος (Peritios, moon of January) (and festival of the month; Peritia)
- Δύστρος (Dystros, moon of February)
- Ξανδικός or Ξανθικός (Xandikos or Xanthikos, moon of March) (and festival of the month; Xanthika, purifying the army, Hesych.)
- Ξανδικός Ἐμβόλιμος (Xandikos Embolimos, intercalated 6 times over a 19-year cycle)
- Ἀρτεμίσιος or Ἀρταμίτιος (Artemisios or Artamitios, moon of April, also a Spartan, Rhodian and Epidaurian month - Artemisiōn was an Ionic month)
- Δαίσιος (Daisios, moon of May)
- Πάνημος or Πάναμος (Panēmos or Panamos, moon of June, also an Epidaurian, Miletian, Samian and Corinthian month)
- Λώιος (Lōios, moon of July - Ὀμολώιος, Homolōios, was an Aetolian, Boeotian and Thessalian month)
- Γορπιαῖος (Gorpiaios, moon of August)
- Ὑπερβερεταῖος (Hyperberetaios, moon of September - Hyperberetos was a Cretan month