Rye whiskey can refer to either of two types of whiskey:
- American rye whiskey, which must be distilled from at least 51 percent rye;
- Canadian whisky, which is often referred to (and labelled as) rye whisky for historical reasons, although it may or may not actually include any rye in its production process.
American rye whiskey 
In the United States, "rye whiskey" is, by law, made from a mash of at least 51 percent rye. (The other ingredients of the mash are usually corn and malted barley.) It is distilled to no more than 160 (U.S.) proof (80% abv), and aged in charred, new oak barrels. The whiskey must be put into such barrels at not more than 125 (U.S.) proof (62.5% abv). Rye whiskey that has been so aged for at least two years may be further designated as "straight", as in "straight rye whiskey".
Rye whiskey was the prevalent whiskey of the northeastern states, especially Pennsylvania and Maryland, but largely disappeared after Prohibition. A few brands, such as Old Overholt, survived it. Today Heaven Hill, Four Roses, Jim Beam, Bulleit, Knob Creek, and Catoctin Creek (among others) also produce rye whiskeys, as does a distillery at Mount Vernon, the home of George Washington, which sells a version of the rye Washington made. Rye is currently undergoing a small but growing revival in the United States. Jack Daniel's has released an unaged rye product, and thus is not legally "whiskey", though an aged version is planned.
Differences between rye and bourbon 
Rye is known for imparting what many call a spicy or fruity flavor to the whiskey. Bourbon, distilled from at least 51% corn, is noticeably sweeter, and tends to be fuller bodied than rye. Due to its distinctive flavor, American rye whiskey is sometimes referred to as America's equivalent of an Islay whisky. As bourbon gained popularity beyond the southern United States, bartenders increasingly substituted it for rye in cocktails like Whiskey sours, Manhattans, and Old Fashioneds, which were originally made with rye. All other things being equal, the character of the cocktail will be drier with rye.
Canadian rye whisky 
Canadian whisky is often referred to as "rye whisky," since historically much of the content was from rye. With no requirement for rye to be used to make whiskies with the legally-identical labels "Canadian Whisky", "Canadian Rye Whisky" or "Rye Whisky" in Canada, provided they "possess the aroma, taste and character generally attributed to Canadian whisky", in some cases the corn-to-rye ratio may be as high as 9:1. Most contemporary Canadian whiskies contain only a fraction of rye, with the exception of Alberta Premium which is one of the very few whiskies made from 100% rye mash.
In contrast with the US "straight rye whiskey" counterpart, a minimum of 3 years aging in small 700 litres (150 imp gal; 180 US gal) wooden barrel is required for the "Canadian Whisky", "Canadian Rye Whisky" and "Rye Whisky" labels, although they need not be new oak, nor charred.
See also 
- ""Standards of Identity for Distilled Spirits," Title 27 Code of Federal Regulations, Pt. 5.22". Frwebgate.access.gpo.gov. Retrieved 2013-04-12.
- ""Rye's Revival," Wine Spectator magazine, July 31, 2008". Winespectator.com. Retrieved 2013-04-12.
- "Catoctin Creek Press Release, March 15, 2010". Catoctincreekdistilling.com. Retrieved 2013-04-12.
- "You are all going to discover the beauty of young rye whiskey," Roundtable Interview, Malt Advocate Volume 16, Number 2, 2007.
- See, e.g. Wondrich, David, Imbibe!: From Absinthe Cocktail to Whiskey Smash, a Salute in Stories and Drinks to "Professor" Jerry Thomas, Pioneer of the American Bar, Perigee Books, 2007. (ISBN 978-0-399-53287-0) At page 241 Wondrich states, in giving the recipe for a Manhattan, that "[a]ll things being equal, a 100-proof rye will make the best Manhattan..."
- ""Canadian Food and Drug Regulations (C.R.C., c. 870) - Canadian Whisky, Canadian Rye Whisky or Rye Whisky (B.02.020.)"". Laws.justice.gc.ca. Retrieved 2013-04-12.
- ""Rye: Situation and Outlook," Agriculture and Agri-Food Canada, Bi-Weekly Bulletin, 2006-06-02 | Volume 19 Number 8 | ISSN 1494-1805 | AAFC No. 2081/E". Agr.gc.ca. 2011-01-30. Retrieved 2013-04-12.