Dewar's 18 Year Old is a blended Scotch whisky that is produced by the Dewar's distillery. The whisky is a blend of multiple single malt and single grain whiskies that have been aged for at least 18 years. The long aging process gives the whisky a rich, complex flavor profile.

The Dewar's 18 Year Old is bottled at a strength of 40% ABV and is said to have notes of honey, vanilla, and oak on the palate, with a long, smooth finish. It is recommended to be enjoyed neat or with a splash of water to bring out the flavors. The whisky has won numerous awards, including a Gold Medal at the International Wine & Spirit Competition in 2007 and a Double Gold Medal at the San Francisco World Spirits Competition in 2010.

In addition to the standard Dewar's 18 Year Old, the distillery also produces a number of limited edition expressions of the whisky, including the Dewar's 18 Year Old Signature, which is a special blend created by Dewar's master blender, and the Dewar's 18 Year Old Double Aged, which is finished in casks that have previously been used to age port wine. These limited edition expressions often have different flavor profiles and higher proofs than the standard Dewar's 18 Year Old.