Interstate 91 (I-91): New Haven to Canada, Miles and Crash Data

How long is I-91?

I-91 is 290.51 miles long in the January 2026 edition of the FHWA Route Log. Wikipedia and Interstate Guide both give 290.37 miles. The gap is a fraction of a mile, and no state row in the Route Log carries an overlap note, so the federal figure is close to what a driver covers from New Haven to the border.

Vermont has the most of it by far: 177.43 miles, about three of every five. Connecticut has 58.17 and Massachusetts 54.91. Two short concurrencies sit inside the Massachusetts miles: half a mile with US 5 near the Springfield and Longmeadow line, and about three miles with Route 2 in Greenfield.

Where I-91 starts and ends

I-91 begins at an interchange with I-95, the Connecticut Turnpike, just east of downtown New Haven. Its northern end is the Derby Line and Rock Island border crossing in Derby Line, Vermont, where the road continues into Canada as Quebec Autoroute 55.

Going north, the cities in order are New Haven, Hartford, Springfield, Northampton and Greenfield, then Brattleboro, White River Junction, St. Johnsbury and Newport in Vermont. From Hartford to St. Johnsbury the highway stays within five miles of the Connecticut River's west bank.

Interstate junctions along I-91

Only five main Interstates touch I-91, listed here from New Haven north. I-95 starts the list at the southern end, I-84 meets it in Hartford and I-90, the Massachusetts Turnpike, meets it in the Springfield area. Vermont has the last two. I-89 meets I-91 at exit 10 in White River Junction, and I-93 comes to its northern end at a three-level stack interchange in St. Johnsbury.

Fatal crashes on I-91

NHTSA's FARS files record 99 deaths in 88 fatal crashes on I-91 from 2020 to 2024, about 20 a year. Measured against its 290.51 miles, I-91 averages 6.8 deaths per 100 route miles per year. The Interstate average is 9.5, and I-91 sits 35th of the 56 routes we rank (1 is the worst rate), in the lower half by rate.

Connecticut accounts for 68 of the 99 deaths on 58.17 miles of road, a rate of 23.4. Massachusetts comes in at 7.3. Vermont, with 177.43 miles and 11 deaths, is at 1.2. Hartford County had 30 deaths and New Haven County 29, so those two counties alone hold more than half the total. Hampden County, around Springfield, is next with 14. Deaths were lowest in 2020, at 13, and highest in 2024, at 25.

Counties with the most I-91 crash deaths

Bridges on I-91

In the 2025 National Bridge Inventory, 406 bridges carry the I-91 main line. Eleven rate Poor, under 3 percent, and 7 of those are in Vermont, which also has the most bridges at 168. Connecticut and Massachusetts have 2 Poor bridges each. Most of the rest rate Fair, 294 against 101 Good, and the median bridge was built in 1965.

The elevated section through downtown Springfield got new decks in a $148 million viaduct rehabilitation. Northbound lanes reopened on December 8, 2017, and most of the work was done by January 2018, about nine months early. In Rockingham, Vermont, a deck truss carries the highway over the Williams River.

Tolls on I-91

As of January 1, 2023, the FHWA toll list had nothing on I-91, so a trip from New Haven to Derby Line costs nothing in tolls. The one special lane in our sources is a high-occupancy vehicle lane in Connecticut that runs from Hartford to Windsor, with its own ramps as far as exit 38. We found no report in Wikipedia or Interstate Guide of a priced lane added since then.

I-91 auxiliary routes

Three numbers branch from I-91, but there are four roads, because two unconnected highways share the I-291 name. The Connecticut I-291 links I-91 to I-84 near Hartford, and the Massachusetts I-291 runs from I-91 in Springfield to the Massachusetts Turnpike. Both I-391, in the Springfield, Chicopee and Holyoke area, and I-691 in Connecticut are under 9 miles.

When I-91 opened

The I-91 number dates from August 14, 1957. Vermont opened its first piece, from the Massachusetts line to Brattleboro, on November 1, 1958, and it was the state's first finished controlled-access highway. Massachusetts completed its section in 1970, and Vermont finished its last sections in 1978.

In Springfield the highway went through the North End, Metro Center and the South End in the 1960s, and it still cuts the city off from its riverfront. At the south end, the I-95 interchange in New Haven went through a long rebuild: the left-hand ramp from I-95 north to I-91 north became a right-hand exit on July 16, 2016, and the work wrapped up in 2017.

I-91 traffic and road conditions

Crashes, lane closures and snow on I-91 change hour by hour, so check the traveler site for the state you are heading into: CTroads in Connecticut, Mass511 in Massachusetts and New England 511 in Vermont, listed below from south to north.

I-91 questions