The Conventionstaler or Konventionstaler, was a standard silver coin in the Austrian Empire and the southern German states of the Holy Roman Empire from the mid-18th to early 19th-centuries. Its most famous example is the Maria Theresa thaler which is still minted today. The Conventionsgulden was equivalent to a 1⁄2 Conventionsthaler.

The Maria Theresa thaler (MTT) is a silver bullion coin and a type of Conventionsthaler that has been used in world trade continuously since it was first minted in 1741. It is named after Maria Theresa who ruled Austria, Hungary, and Bohemia from 1740 to 1780 and is depicted on the coin.