This is a list of numbered roads in the United Counties of Leeds and Grenville, Ontario.
| County Road # | Local Name(s) | Southern/Western Terminus | Northern/Eastern Terminus | Settlements served | Additional Notes |
|---|---|---|---|---|---|
| 1 | County Road 1 Kitley/South Elmsley Townline Road Anglican Church Road Rideau Ferry Road |
County Road 29 | the Rideau Canal | Toledo, Lombardy, Rideau Ferry | |
| 2 | County Road 2 | Deer Ridge Drive | Marine Station Road | Gananoque, Legge, Ebenezer, Escott, Sherwood Springs, Brockville, Maitland, Blue Church, Prescott, Wexford, Johnstown, Cardinal | formerly  Highway 2 running from Windsor to the Ontario-Quebec border;a.k.a. King Street in Gananoque, King Street in Brockville, and King Street in Prescott; not to be confused with Highway 2 between Gananoque's eastern town limits and  Highway 401
|
| 3 | Reynolds Road Prince Street Outlet Road Bryan Road |
Thousand Islands Parkway | County Road 33 | Selton, Lansdowne, Dulcemaine, Outlet, Long Point | |
| 4 | Warburton Road Blue Mountain Road Rockfield Road Sly Road Quabbin Road |
County Road 3 | County Road 2 | Warburton, Rockfield, Quabbin, Mallorytown | |
| 5 | Mallorytown Road County Road 5 |
Thousand Islands Parkway |  Highway 15
|
Mallorytown Landing, Caintown, McIntosh Mills, Athens, Plum Hollow, Newboyne | a.k.a. Mill Street, Main Street and Elgin Street in Athens |
| 6 | North Augusta Road | County Road 26 | County Road 15 | Rows Corners, Manhard, North Augusta | |
| 7 | Greenbush Road County Road 7 |
County Road 29 | County Road 16 | Greenbush, Rocksprings, Crystal | |
| 8 | Main Street Toledo Road Line 6 Road |
Highway 15
|
County Road 29 | Elgin, Phillipsville, Bellamys Mills, Toledo | |
| 9 | Chaffeys Lock Road | Rideau Canal | Highway 15
|
Chaffeys Lock | |
| 10 | Perth Road | Frontenac County limits | Lanark County limits | Blairs Settlement, Westport | |
| 11 | Jones Falls Road | Simpson Road | Highway 15
|
Jones Falls | |
| 12 | Salem Road | Wolfe Lake Road | County Road 10 | Salem, Westport | |
| 13 | South Lake Road | Boundary Road | County Road 32 | Springfield | |
| 14 | Narrows Lock road | County Road 42 | Rideau Canal | Crosby, Narrows Lock | |
| 15 | Church Street County Road 15 Reid Street |
County Road 2 | Rideau Canal | Maitland, Stones Corners, North Augusta, Wolford Centre, Hemlock Corners, Merrickville | |
| 16 | County Road 16 | County Road 29 | County Road 15 | Jasper, Eastons Corners | not to be confused with  Highway 16
|
| 17 | Jasper Road | County Road 16 | Lanark County limits | Jasper | |
| 18 | County Road 18 Clothier Street |
Prescott town limits | Sanders Street, Kemptville | Sparkle City, Roebuck, McRoberts Corner, Bishops Mills, Hutchins Corners, Kemptville | |
| 19 | Rideau River Road | County Road 24 | Ottawa city (old Carleton County) limits | Kemptville, Besley Woods | |
| 20 | Oxford Station Road Town Line Road Slater Road Dillabaugh Road |
County Road 18 | Boundary Road | East Oxford, Oxford Station, Millars Corners, Heckston | |
| 21 | County Road 21 Shanly Road |
County Road 15 | Byker Road | Throoptown, Roebuck, Spencerville, Shanly | |
| 22 | County Road 22 Gower Drive |
County Road 2 | County Road 19 | Cardinal, Brouseville, Pittston, Shanly, Heckston, Pelton Corner | |
| 23 | River Road Burritts Rapids Road |
County Road 43 | County Road 43 | Burritts Rapids | |
| 24 | Vanburen Street | Prescott Street, Kemptville | County Road 43 | Kemptville | |
| 25 | Guy Road | County Road 18 | County Road 43 | Swan Crossing | |
| 26 | 3rd Concession Road | County Road 6 | County Road 18 | Rows Corners, Bethel, Stones Corners, Maynard | |
| 27 | Yonge Mills Road Main Street Centennial Road |
County Road 2 | County Road 29 | Yonge Mills, Lyn | |
| 28 | County Road 28 | County Road 29 | County Road 6 | Glen Buell, New Dublin, Bellamys | |
| 29 | County Road 29 | County Road 27 | Lanark County limits | Tincap, Glen Bluell, Forthton, Addison, Lehighs Corners, Frankville, Toledo, Newbliss, Shanes | formerly  Highway 29 running from Brockville to Arnprior
|
| 30 | Addison Road | County Road 42 | County Road 29 | Anoma Lea, Addison | |
| 31 | Blue Church Road | County Road 2 | County Road 26 | Blue Church | |
| 32 | Stone Street County Road 32 |
County Road 2 | Highway 15;
|
Gananoque, Cheeseborough, Taylor, Berrytown | formerly  Highway 32
|
| 33 | Lyndhurst Road | Highway 15
|
County Road 42 | Sweets Corners, Lyndhurst | |
| 34 | Hiscocks Road Eden Grove Road |
County Road 2 | County Road 3 | Emery, Eden Grove, Lansdowne | |
| 35 | Station Road | County Road 32 | County Road 34 | Gananoque Junction | |
| 36 | Mountain Road | County Road 12 | Lanark County limits | Westport | |
| 37 | Howe Island Ferry Road | the St. Lawrence River | County Road 2 | the Howe Island ferry wharf | |
| 38 | Briton-Houghton Bay Road | Highway 15
|
Willis Wharf | Mill Pond, Big Rideau Lake | |
| 39 | County Park Road | Charleston Lake | County Road 40 | Charleston | |
| 40 | King Street Charleston Road Elgin Street South |
Cedar Park Lane | County Road 5 | Charleston, Glen Morris, Athens | |
| 41 | County Road 41 | County Road 15 | County Road 16 | Hemlock Corners | |
| 42 | County Road 42 | County Road 12 | County Road 29 | Westport, Newboro, Crosby, Forfar, Philipsville, Delta, Soperton, Athens, Glen Elbe, Forthton | formerly  Highway 42; a.k.a. Main Street in Athens, King Street in Delta and Drummond Street in Newboro
|
| 43 | County Road 43 | County Road 15 | Boundary Road | Merrickville, Actons Corners, Kemptville | formerly  Highway 43 running from Perth east to Alexandria
|
| 44 | County Road 44 | Highway 16
|
the Rideau Canal | Crystal Rock, Glen Smail, Spencerville, Groveton, Van Allens, Kemptville | Former alignment of Highway 16 prior to the construction of Highway 16 New/ Highway 416 in the 1990s;a.k.a. Prescott Street and Sanders Street in Kemptville |
| 45 | Brockchem Road | County Road 2 | CN rail yard, Maitland | Du Pont Canada nylon factory | |
| 46 | Lyn Road Main Street Perth Street County Road 46 |
County Road 2 | County Road 29 | Lyn, Seeley | |
| 47 | Main Street | Highway 15
|
Highway 15
|
Seeley's Bay |