# List of lettered highways in Maine

From 1914 to 1925, Maine used a system of lettered highways to designate cross-state routes. It is unclear as to whether the system lasted through the recognition of pole-marked auto trails by the State Highway Commission in 1919, both systems were abandoned by 1925 in favor of the New England interstate highway system.

## List of routes

| Route | From | Through | To | Modern designation |
| A | Kittery | York, Wells, Kennebunk, Biddeford, Saco, Scarboro, South Portland | Portland | US 1 |
| B | Fryeburg | Bridgton, Naples, Casco, Raymond, Windham, Westbrook | Portland | US 302 |
| C | Portland | Falmouth, Cumberland, Yarmouth, Freeport, Brunswick, West Bath | Bath | US 1 |
| D | Woolwich | Wiscasset, Edgecomb, Alna, Newcastle, Damariscotta, Nobleboro, Waldoboro, Warren, Thomaston, Rockland, Rockport, Camden, Lincolnville, Northport | Belfast | US 1 |
| E | Portland | Falmouth, Cumberland, Gray, New Gloucester, Auburn, Lewiston, Greene, Monmouth, Winthrop, Manchester | Augusta | SR 100, US 202 |
| F | Auburn | Turner, Livermore, East Livermore, Jay, Wilton, Farmington, Strong, Avon, Phillips, Sandy River Plantation | Rangely | SR 4 |
| G | Augusta | Sidney, Belgrade, Oakland | Waterville | SR 27, SR 11 |
| H | Augusta | Vassalboro, Winslow, Waterville, Fairfield, Skowhegan, Norridgewock, Madison, Anson, Embden, Solon, Bingham, Moscow, Caratunk Plantation, The Forks Plantation, West Forks Plantation, Johnson Mountain, Parlin Pond, Jackman Plantation, Moose River Plantation, Dennistown Plantation, Sandy Bay Plantation | Quebec Line | US 201, US 201A, US 201 |
| I | Fairfield | Benton, Clinton, Burnham, Pittsfield, Palmyra, Newport, Etna, Carmel, Herman | Bangor | SR 100, US 2 |
| J | Newport | Corinna, Dexter, Dover, Foxcroft, Guilford, Abbot, Monson, Shirley | Greenville | SR 7, SR 23, SR 6 |
| K | Bangor | Veazie, Orono, Oldtown, Milford, Greenbush, Passadumkeag, Enfield, Lincoln, Winn, Mattawamkeag, Molunkus, Medway, Stacyville, Sherman, Crystal, Island Falls, Dyer Brook, Merrill, Smyrna, Ludlow, New Limerick, Houlton, Littleton, Monticello, Bridgewater, Blaine, Mars Hill, Easton, Presque Isle, Caribou, Connor, Cyr, Van Buren, Grand Isle, Madawaska, Frenchville | Fort Kent | US 2, US 1 |
| L | Belfast | Searsport, Stockton Springs, Prospect, Frankfort, Winterport, Hampden | Bangor | US 1, US 1A |
| M | Bangor | Brewer, Holden, Dedham, Ellsworth | Trenton | US 1A, SR 3 |
| N | Ellsworth | Hancock, Franklin, Sullivan, Gouldsboro, Steuben, Milbridge, Cherryfield, Harrington, Columbia, Columbia Falls, Jonesboro, Whitneyville, Machias, East Machias, Whiting, Trescott, Edmunds, Dennysville, Pembroke, Perry, Robbinstown | Calais | US 1 |
| N Spur | Perry | | Eastport | SR 190 |
| N Spur | Whiting | Trescott | Lubec | SR 189 |
| N Spur | Columbia Falls | Addison | Jonesport | SR 187 |
| O | Livermore | Canton, Peru, Dixfield, Mexico, Rumford, Hanover, Newry, Bethel, Gilead | New Hampshire state line | SR 108, Main Street, US 2 |
| P | Augusta | Chelsea, Whitefield, Windsor, Jefferson, Somerville, Washington, Union, Hope, Rockport | Rockland | SR 17 |
| Q | Augusta | Hallowell, Farmingdale, Gardiner, Richmond, Bowdoinham, Topsham | Brunswick | US 201, SR 24 |
| R | Augusta | Vassalboro, China, Palermo, Liberty, Montville, Searsmont, Morrill, Waldo | Belfast | US 202, SR 3 |
| S | Gray | New Gloucester, Poland, Mechanic Falls, Oxford, Norway, Paris, Woodstock, Greenwood | Bethel | SR 26 |
| T | Newry | Grafton, Upton | New Hampshire state line | SR 26 |
| U* | Biddeford | Kennebunkport, Lyman, Alfred, Sanford, Lebanon | New Hampshire state line | SR 111, US 202 |
| V* | Norridgewock | Mercer, New Sharon | Farmington | US 2 |
| W* | Belgrade Depot | Rome | New Sharon | SR 27 |
| X | Bangor | Glenburn, Kenduskeag, Corinth, Charleston, Garland, Hermon | Dover | ME 15 |
* Indicates route not finalized by 1914 report