|Centuries:||2nd century – 3rd century – 4th century|
|Decades:||240s 250s 260s – 270s – 280s 290s 300s|
|Years:||272 273 274 – 275 – 276 277 278|
|275 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1028|
|Chinese calendar||甲午年 (Wood Horse)
2971 or 2911
— to —
乙未年 (Wood Goat)
2972 or 2912
|Coptic calendar||−9 – −8|
|- Vikram Samvat||331–332|
|- Shaka Samvat||197–198|
|- Kali Yuga||3376–3377|
|Iranian calendar||347 BP – 346 BP|
|Islamic calendar||358 BH – 357 BH|
|Minguo calendar||1637 before ROC
|Seleucid era||586/587 AG|
|Thai solar calendar||817–818|
Year 275 (CCLXXV) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Aurelianus and Marcellinus (or, less frequently, year 1028 Ab urbe condita). The denomination 275 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.
- Emperor Aurelian prepares a campaign against the Sassanids in Asia Minor. In Thrace, while waiting to cross the Bosphorus with his army, he hands out severe punishments to corrupt soldiers and makes a list of high-ranking officers marked for execution.
- September – Aurelian falls victim to a conspiracy of the Praetorian Guard and is murdered near Byzantium (Turkey).
- September 25 – Marcus Claudius Tacitus is proclaimed Emperor by the Senate, his half brother Marcus Annius Florianus becomes Praetorian prefect.
- Gaul is pillaged by the Franks and the Alemanni.
- The Pallava dynasty begins in Southern India.
- Eusebius of Caesarea (approximate date)
- Saint George, soldier of the Roman Empire and later Christian martyr (or 281, approximate date)
- Aurelian, Roman emperor
- Mani, founder of Manichaeism (approximate date)
- Xiang Xiu
- Zenobia, queen of the Palmyrene Empire (b. 240)