The year 550 BC was a year of the pre-Julian Roman calendar. In the Roman Empire, it was known as year 204 Ab urbe condita. The denomination 550 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
| Millennium: | 1st millennium BC |
|---|---|
| Centuries: |
|
| Decades: |
|
| Years: |
|
| Gregorian calendar | 550 BC DL BC |
| Ab urbe condita | 204 |
| Ancient Egypt era | XXVI dynasty, 115 |
| - Pharaoh | Amasis II, 21 |
| Ancient Greek era | 57th Olympiad, year 3 |
| Assyrian calendar | 4201 |
| Balinese saka calendar | N/A |
| Bengali calendar | −1142 |
| Berber calendar | 401 |
| Buddhist calendar | −5 |
| Burmese calendar | −1187 |
| Byzantine calendar | 4959–4960 |
| Chinese calendar | 庚戌年 (Metal Dog) 2148 or 1941 — to — 辛亥年 (Metal Pig) 2149 or 1942 |
| Coptic calendar | −833 – −832 |
| Discordian calendar | 617 |
| Ethiopian calendar | −557 – −556 |
| Hebrew calendar | 3211–3212 |
| Hindu calendars | |
| - Vikram Samvat | −493 – −492 |
| - Shaka Samvat | N/A |
| - Kali Yuga | 2551–2552 |
| Holocene calendar | 9451 |
| Iranian calendar | 1171 BP – 1170 BP |
| Islamic calendar | 1207 BH – 1206 BH |
| Javanese calendar | N/A |
| Julian calendar | N/A |
| Korean calendar | 1784 |
| Minguo calendar | 2461 before ROC 民前2461年 |
| Nanakshahi calendar | −2017 |
| Thai solar calendar | −7 – −6 |
| Tibetan calendar | 阳金狗年 (male Iron-Dog) −423 or −804 or −1576 — to — 阴金猪年 (female Iron-Pig) −422 or −803 or −1575 |