Prior to the New England Interstate Routes, through routes were mainly marked with colored bands on telephone poles. These were assigned by direction (red for east-west, blue for north-south and yellow for imtermediate or diagonal routes). The Massachusetts Highway Commission convinced the rest of southern New England and New York to use this system in 1915 (New Hampshire and Vermont already had their own schemes, and Maine also opted out), and it was the main system until 1922.<ref>US-5: A Highway to History</ref>
The New England Interstate system, while limited to New England, was designed for expansion to the whole country. One- and two-digit numbers were assigned to major interstate routes, with three-digit routes for state routes (marked in a rectangle, with the state abbreviation below the number). In general, odd numbers ran east-west and even numbers ran north-south. The main exception was Route 1, which was to run along the Atlantic coast from Florida to Calais, Maine. A few of the major auto trails were not to be assigned numbers, instead being marked with letters - for instance, L for the Lincoln Highway and R for the Roosevelt International Highway.<ref name="nyt April 16"/>
| New England Route
| Current Routes
| Endpoints
|
| Image:New England 1.svg Route 1
| Image:US 1.svg
| New York, NY to Calais, ME (towards Saint John, New Brunswick)
|
| Image:New England 1A.svg Route 1A
| Image:Rhode Island 3.svg
| Westerly, RI to Providence, RI
|
| Image:New England 2.svg Route 2
| Image:US 5.svg
| New Haven, CT (Route 1) to Derby Line, VT (towards Sherbrooke, Quebec)
|
| Image:New England 2A.svg Route 2A
| Image:Vermont 5A.svg
| West Burke, VT to Derby, VT
|
| Image:New England 3.svg Route 3
| Image:US 6.svg
| Bedford, NY (Route 22) to Provincetown, MA
|
| Image:New England 4.svg Route 4
| Image:US 7.svg
| New York, NY to Highgate Springs, VT (towards Montreal, Quebec) Not signed as Route 4 in New York (see Route 22).
|
| Image:New England 5.svg Route 5
| Image:US 20.svg
| Albany, NY to Boston, MA (Routes 1 - 6 - 7 - 28)
|
| Image:New England 6.svg Route 6
| Image:US 3.svg Image:MA Route 3.svg
| Orleans, MA (Route 3) to Colebrook, NH (Route 26)
|
| Image:New England 6A.svg Route 6A
| Image:MA Route 3A.svg
| Kingston, MA to Quincy, MA
|
| Image:New England 6A.svg Route 6A
| Image:NH Route 3A.svg
| Franklin, NH to Plymouth, NH
|
| Image:New England 6B.svg Route 6B
| Image:MA Route 38.svg
| Cambridge, MA to Lowell, MA
|
| Image:New England 7.svg Route 7
| Image:NY-2.svg Image:MA Route 2.svg
| Troy, NY to Boston, MA (Routes 1 - 5 - 6 - 28)
|
| Image:New England 8.svg Route 8
| Image:Connecticut Highway 8.png Image:MA Route 8.svg Image:Vermont 8.svg
| Stratford, CT (Route 1) to Wilmington, VT (Route 9)
|
| Image:New England 9.svg Route 9
| Image:NY-7.svg Image:Vermont 9.svg Image:NH Route 9.svg Image:MA Route 9.svg
| Troy, NY to Wells, ME (Route 1)
|
| Image:New England 10.svg Route 10
| Image:Connecticut Highway 10.png Image:MA Route 10.svg Image:NH Route 10.svg
| Old Saybrook, CT (Route 1) to Littleton, NH (Route 18)
|
| Image:New England 11.svg Route 11
| Image:Vermont 11.svg Image:NH Route 11.svg Image:MA Route 11.svg Image:MA Route 111.svg
| Manchester, VT (Route 4) to Biddeford, ME (Route 1)
|
| Image:New England 12.svg Route 12
| Image:Connecticut Highway 12.png Image:MA Route 12.svg Image:NH Route 12.svg Image:Vermont 12.svg
| New London, CT (Route 1) to Derby, VT (Route 2)
|
| Image:New England 12A.svg Route 12A
| Image:Vermont 12A.svg
| Randolph, VT to Northfield, VT
|
| Image:New England 12B.svg Route 12B
| Image:Vermont 14.svg
| Hardwick, VT to Coventry, VT
|
| Image:New England 13.svg Route 13
| Image:US 4.svg
| Whitehall, NY to White River Junction, VT (Routes 2 - 14)
|
| Image:New England 14.svg Route 14
| Image:Vermont 14.svg Image:US 2.svg
| Burlington, VT (Routes 4 - 15 - 30) to White River Junction, VT (Routes 2 - 13)
|
| Image:New England 15.svg Route 15
| Image:Vermont 15.svg Image:US 2.svg
| Burlington, VT (Routes 4 - 14 - 30) to Houlton, ME (towards Fredericton, New Brunswick)
|
| Image:New England 16.svg Route 16
| Image:NH Route 16.svg
| Portsmouth, NH (Route 1) to Errol, NH (Route 26)
|
| Image:New England 17.svg Route 17
| Image:NY-23.svg Image:MA Route 23.svg Image:US 7.svg Image:US 44.svg Image:Connecticut Highway 2.png
| Hudson, NY to Westerly, RI (Route 1) Not signed as Route 17 in New York (see Route 23).
|
| Image:New England 18.svg Route 18
| Image:US 2.svg Image:Vermont 18.svg Image:NH Route 18.svg Image:US 302.svg
| Portland, ME (Routes 1 - 25 - 26) to Montpelier, VT (Routes 12 - 14 - 25)
|
| Image:New England 19.svg Route 19
| Image:US 302.svg Image:MA Route 11.svg Image:MA Route 196.svg
| Bethlehem, NH (Route 10 - 18) to Brunswick, ME (Route 1) In the 1922 plan but was never signed.
|
| Image:New England 20.svg Route 20
| Image:US 201.svg
| Brunswick, ME (Route 1) to Jackman, ME (towards Quebec City, Quebec)
|
| Image:New England 21.svg Route 21
| Image:US 44.svg
| Poughkeepsie, NY to Amenia, NY (Route 4 - 22) Not an official New England route designation but numbered by New York to be consistent with the system.
|
| Image:New England 22.svg Route 22
| Image:NY-22.svg
| New York, NY (Route 1) to Hillsdale, NY (Route 23) Not an official New England route designation but numbered by New York to be consistent with the system. The section from Manhattan to Amenia was part of Route 4.
|
| Image:New England 23.svg Route 23
| Image:NY-23.svg Image:MA Route 23.svg
| Hudson, NY to South Egremont, MA (Route 4) Not an official New England route designation but numbered by New York to be consistent with the system. This segment was planned to be part of Route 17.
|
| Image:New England 24.svg Route 24
| Image:US 1.svg
| Calais, ME to Madawaska, ME 1922 plan was routed Portland, ME to Greenville, ME
|
| Image:New England 25.svg Route 25
| Image:US 302.svg Image:NH Route 25.svg Image:MA Route 25.svg
| Montpelier, VT (Routes 12 - 14 - 18) to Portland, ME (Routes 1 - 18 - 26)
|
| Image:New England 25A.svg Route 25A
| Image:Vermont 25.svg
| West Topsham, VT to Bradford, VT
|
| Image:New England 26.svg Route 26
| Image:MA Route 26.svg Image:NH Route 26.svg Image:Vermont 26.svg
| Portland, ME (Routes 1 - 18 - 25) to Colebrook, NH (Route 6)
|
| Image:New England 28.svg Route 28
| Image:MA Route 28.svg Image:NH Route 28.svg
| Buzzards Bay, MA (Route 3) to Ossipee, NH (Route 16)
|
| Image:New England 30.svg Route 30
| Image:NY-22A.svg Image:Vermont 30.svg Image:US 7.svg Image:US 2.svg
| Granville, NY to Alburgh, VT
|
| Image:New England 30A.svg Route 30A
| Image:Vermont 22A.svg
| Fair Haven, VT to Vergennes, VT
|
| Image:New England 32.svg Route 32
| Image:Connecticut Highway 32.png Image:MA Route 32.svg Image:NH Route 32.svg
| Groton, CT (Route 1) to Newport, NH (Route 11)
|
| Image:New England 32A.svg Route 32A
| Image:US 202.svg Image:NH Route 103.svg
| Bradford, NH to Hopkinton, NH
|