| Millennium: | 1st millennium BC |
|---|---|
| Centuries: | 4th century BC – 3rd century BC – 2nd century BC |
| Decades: | 270s BC 260s BC 250s BC – 240s BC – 230s BC 220s BC 210s BC |
| Years: | 245 BC 244 BC 243 BC – 242 BC – 241 BC 240 BC 239 BC |
| 242 BC by topic | |
| Politics | |
| State leaders – Sovereign states | |
| Birth and death categories | |
| Births – Deaths | |
| Establishments and disestablishments categories | |
| Establishments – Disestablishments | |
| Gregorian calendar | 242 BC |
| Ab urbe condita | 512 |
| Armenian calendar | N/A |
| Bahá'í calendar | -2085 – -2084 |
| Bengali calendar | -834 |
| Berber calendar | 709 |
| Buddhist calendar | 303 |
| Burmese calendar | -879 |
| Byzantine calendar | 5267 – 5268 |
| Chinese calendar | [[Sexagenary cycle|]]年 (2395/2455) — to —
[[Sexagenary cycle|]]年(2396/2456) |
| Coptic calendar | -525 – -524 |
| Ethiopian calendar | -249 – -248 |
| Hebrew calendar | 3519 – 3520 |
| Hindu calendars | |
| - Bikram Samwat | -185 – -184 |
| - Shaka Samvat | N/A |
| - Kali Yuga | 2860 – 2861 |
| Holocene calendar | 9759 |
| Iranian calendar | 863 BP – 862 BP |
| Islamic calendar | 890 BH – 889 BH |
| Japanese calendar | |
| Korean calendar | 2092 |
| Thai solar calendar | 302 |