Saône-et-Loire (French pronunciation: [sonelwaʁ]; Arpitan: Sona-et-Lêre) is a department in the Bourgogne-Franche-Comté region in France.

When it was formed during the French Revolution, as of March 4, 1790 in fulfillment of the law of December 22, 1789, the new department combined parts of the provinces of southern Burgundy and Bresse, uniting lands that had no previous common history nor political unity and which have no true geographical unity.

In the west, the department is composed of the hills of the Autunois, the region around Autun, in the southwest the Charollais, and the Mâconnais in the south.

It then makes its way in the opposite direction, forming the southwest border of the department, and eventually draining into the Atlantic Ocean.

In the west, its industrial heart is in Le Creusot and Montceau-les-Mines, formerly noted for their coal mines and metallurgy.