Stratos Pagioumtzis (Greek: Στράτος Παγιουμτζής 1904 – 16 November 1971) was a Greek rebetiko singer, also known with the nickname Stratos the sluggard (Στράτος ο τεμπέλης) or simply Stratos.
Pagioumtzis was born in Ayvalık of Asia Minor and migrated to Greece before the Greco-Turkish war of 1919–1922. He settled in the port city of Piraeus and supported himself by working as a fisherman and later as a supplier of provisions to moored ships. He started to sing professionally in the late 1920s and his first recordings appeared in 1933. In 1934, together with Yiorgos Batis, Anestis Delias and Markos Vamvakaris, he founded the rebetiko quartet, I Tetras i Xakousti tou Peiraios (Greek: Η τετράς η ξακουστή του Πειραιώς, literally Piraeus' famous quartet). In 1937, during the Metaxas dictator regime, he was convicted of drug use and was expelled to the Cycladic island of Sifnos.
Pagioumtzis had a beautiful voice which made him widely known. He is considered as the greatest singer of the classical rebetiko era. Pagioumtzis recorded over 400 songs with his voice and worked with many well-known composers such as Vassilis Tsitsanis, Giannis Papaioannou, Stelios Keromytis, Bayianteras, Panagiotis Toundas and Vangelis Papazoglou. Vassilis Tsitsanis once said that Pagioumtzis had nightingales in his throat.