# List of highways numbered 21

For roads named A21 see ; List of A21 roads Route 21, or Highway 21, can refer to:

## International

* E21 European route E21

## Australia

* Chandler Highway
* Toowoomba Connection Road (QLD)
* – Kakadu Highway

## Austria

* Wiener Außenring Autobahn

## Cambodia

* National Road 21 (Cambodia)

## Canada

* Alberta Highway 21
* British Columbia Highway 21
* Manitoba Highway 21
* Newfoundland and Labrador Route 21
* Ontario Highway 21
* Prince Edward Island Route 21
* Saskatchewan Highway 21

## Costa Rica

* National Route 21

## Cuba

* Highway 6–21

## Czech Republic

* I/21 Highway; Czech: Silnice I/21

## Greece

* EO21 road

## Hungary

* Main road 21 (Hungary)

## India

* National Highway 21 (India)

## Iran

* Road 21

## Ireland

* N21 road (Ireland)

## Italy

* Autostrada A21

## Japan

* Japan National Route 21

## Korea, South

* National Route 21

## Moldova

* M21 highway (Moldova)

## New Zealand

* New Zealand State Highway 21

## Paraguay

* National Route 21

## Turkey

* O-21, a motorway in Turkey running from Kemerhisar, Niğde Province to Tarsus, Mersin Province.

## United Kingdom

* British A21 (Hastings-London)
* A21 road (Northern Ireland)

## United States

* U.S. Route 21
* Alabama State Route 21
* Arkansas Highway 21
** Arkansas Highway 21E (former)
** Arkansas Highway 21W (former)
* California State Route 21 (former)
** County Route A21 (California)
** County Route E21 (California)
** County Route G21 (California)
** County Route J21 (California)
** County Route S21 (California)
* Colorado State Highway 21
* Connecticut Route 21
* Florida State Road 21
** County Road 21B (Clay County, Florida)
** County Road 21B (Duval County, Florida)
** County Road 21D (Duval County, Florida)
** County Road 21 (Marion County, Florida)
** County Road 21 (Putnam County, Florida)
* Georgia State Route 21
* Hawaii Route 21 (former)
* Idaho State Highway 21
* Illinois Route 21
* Indiana State Road 21 (former)
* Iowa Highway 21
* Kentucky Route 21
* Louisiana Highway 21
* Maryland Route 21
* Massachusetts Route 21
* M-21 (Michigan highway)
* Minnesota State Highway 21
** County Road 21 (Anoka County, Minnesota)
** County Road 21 (Hennepin County, Minnesota)
** County Road 21 (Scott County, Minnesota)
* Mississippi Highway 21
* Missouri Route 21
* Montana Highway 21
* Nebraska Highway 21
** Nebraska Spur 21B
** Nebraska Spur 21C
* Nevada State Route 21 (former)
* New Jersey Route 21
** County Route C21 (Bergen County, New Jersey)
** County Route 21 (Monmouth County, New Jersey)
* New Mexico State Road 21
* New York State Route 21
** County Route 21 (Allegany County, New York)
** County Route 21 (Chautauqua County, New York)
** County Route 21 (Columbia County, New York)
*** County Route 21B (Columbia County, New York)
*** County Route 21C (Columbia County, New York)
** County Route 21 (Delaware County, New York)
** County Route 21 (Dutchess County, New York)
** County Route 21 (Erie County, New York)
** County Route 21 (Essex County, New York)
** County Route 21 (Genesee County, New York)
** County Route 21 (Hamilton County, New York)
** County Route 21 (Herkimer County, New York)
** County Route 21 (Lewis County, New York)
** County Route 21 (Oneida County, New York)
** County Route 21 (Ontario County, New York)
** County Route 21 (Orange County, New York)
** County Route 21 (Oswego County, New York)
** County Route 21 (Otsego County, New York)
** County Route 21 (Putnam County, New York)
** County Route 21 (Rensselaer County, New York)
** County Route 21 (Saratoga County, New York)
** County Route 21 (Schoharie County, New York)
** County Route 21 (Suffolk County, New York)
** County Route 21 (Sullivan County, New York)
** County Route 21 (Ulster County, New York)
** County Route 21 (Washington County, New York)
** County Route 21 (Westchester County, New York)
** County Route 21 (Wyoming County, New York)
** County Route 21 (Yates County, New York)
* North Carolina Highway 21 (former)
* North Dakota Highway 21
* Ohio State Route 21
* Pennsylvania Route 21
* South Carolina Highway 21 (1920s) (former)
* South Dakota Highway 21
* Tennessee State Route 21
* Texas State Highway 21
** Texas State Highway Loop 21
** Farm to Market Road 21
** Texas Park Road 21
* Utah State Route 21
* State Route 21 (Virginia 1918-1933) (former)
* Washington State Route 21
** Primary State Highway 21 (Washington) (former)
** Secondary State Highway 21B (Washington) (former)
** Secondary State Highway 21C (Washington) (former)
* County Route 21 (Jackson County, West Virginia)
** County Route 21 (Kanawha County, West Virginia)
** County Route 21 (Wirt County, West Virginia)
** County Route 21 (Wood County, West Virginia)
* Wisconsin Highway 21

### Territories

* Puerto Rico Highway 21