|Millennium:||1st millennium BC|
|Centuries:||6th century BC – 5th century BC – 4th century BC|
|Decades:||520s BC 510s BC 500s BC – 490s BC – 480s BC 470s BC 460s BC|
|Years:||496 BC 495 BC 494 BC – 493 BC – 492 BC 491 BC 490 BC|
|493 BC by topic|
|Gregorian calendar||493 BC|
|Ab urbe condita||261|
|Ancient Egypt era||XXVII dynasty, 33|
|- Pharaoh||Darius I of Persia, 29|
|Ancient Greek era||71st Olympiad, year 4|
|Chinese calendar||丁未年 (Fire Goat)
2204 or 2144
— to —
戊申年 (Earth Monkey)
2205 or 2145
|Coptic calendar||−776 – −775|
|Ethiopian calendar||−500 – −499|
|- Vikram Samvat||−436 – −435|
|- Shaka Samvat||N/A|
|- Kali Yuga||2609–2610|
|Iranian calendar||1114 BP – 1113 BP|
|Islamic calendar||1148 BH – 1147 BH|
|Minguo calendar||2404 before ROC
|Thai solar calendar||50–51|
|Wikimedia Commons has media related to 493 BC.|
Year 493 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Auruncus and Viscellinus (or, less frequently, year 261 Ab urbe condita). The denomination 493 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.
- The Athenian people elect Themistocles as archon, the chief judicial and civilian executive officer in Athens. He favours resistance against the Persians.
- Themistocles starts the construction of a fortified naval base at Piraeus, the port town of Athens.
- Among the refugees arriving from Ionia after the collapse of the Ionian Revolt is a chief named Miltiades, who has a fine reputation as a soldier. Themistocles makes him a general in the Athenian army.
- The secession of the plebs concludes.
- The Roman army, led by Postumus Cominius Auruncus defeats the Volsci and the Romans capture the towns of Longula, Pollusca and Corioli. Gaius Marcius distinguishes himself in the battle for Corioli, and earns the cognomen Coriolanus.
- During his second consulate, the Roman consul Spurius Cassius Viscellinus concludes a treaty with the Latin League, the Foedus Cassianum, confirming Roman primacy in Latium.
- The Athenian poet Phrynicus produces a tragedy on the Fall of Miletus. The Athenian authorities ban the play from further production on the grounds of impiety.