U.S. Route 44 (US 44) is an east–west U.S. Highway running from Salisbury to Putnam.

From the New York state line at Salisbury to the Rhode Island state line at Putnam, US 44 runs for a total of 106.03 miles (170.64 km) in Connecticut. Most of US 44 is known in the state as the Jonathan Trumbull Highway. It begins as rural arterial road in Litchfield county, going through the towns of North Canaan, Norfolk, Colebrook, Winchester, Barkhamsted, and New Hartford. It is a 2-lane road with 4-lane sections in Winchester. In Canton, US 44 is joined by US 202 and becomes a mostly 4-lane principal arterial road serving the Hartford metro area. US 44 continues through Simsbury, Avon, and W. Hartford. US 202 splits from US 44 in Avon following the route of Route 10 after overlapping for 5.3 miles (8.5 km). US 44 then enters the city of Hartford along Albany Avenue, then goes up onto I-84/US 6 to cross the Connecticut River on the Bulkeley Bridge. In E. Hartford, US 44 then returns to surface roads right after crossing the river. It becomes a 2-lane minor arterial road through Manchester, Bolton, Coventry, and Mansfield, then becomes a rural road through Willington, Ashford, Eastford, Pomfret, and Putnam. In Manchester, US 44 overlaps with US 6 for 6.9 miles (11.1 km) up to Bolton until just after the eastern terminus of I-384. This segment of US 44 up to Willington is known as the Boston Turnpike while the segment approaching Rhode Island is called Providence Pike.

Most of the alignment of modern US 44 in Connecticut was at one time part of an early network of turnpikes in the state during the 19th century. From the New York state line at Salisbury to the village of Lakeville, the route was the westernmost section of the Salisbury and Canaan Turnpike. Between North Canaan and New Hartford, modern US 44 was known as the Greenwoods Turnpike. The southeastward continuation of the Greenwoods road to the West Hartford-Hartford line was known as the Talcott Mountain Turnpike. From East Hartford to Eastford, the Boston Turnpike was chartered mostly along modern US 44 as the direct route from Hartford to Boston. The Boston Turnpike differed from modern US 44 by using a more direct route between Eastford and Pomfret Center along modern Route 244, while US 44 runs via the village of Abington. Past Pomfret Center, the Boston Turnpike diverged from modern US 44 heading northeast across the town of Thompson. The route through Putnam to the Rhode Island state line was a different turnpike road known as the Pomfret and Killingly Turnpike.

In 1922, the New England states designated route numbers on its main roads. Route 101 was assigned as the route used by the Pomfret and Killingly Turnpike (modern US 44) to Pomfret Center, then modern US 44 to Phoenixville via Abington (short portions of two other turnpike roads), then a road southward from Phoenixville to South Chaplin (modern Route 198), ending at New England Route 3. The direct road connecting Phoenixville to Bolton Notch was designated as Route 109. From Hartford to Bolton Notch, modern US 44 was at the time known as New England Route 3. West of Hartford, modern US 44 was designated as part of New England Route 17, which stretched in Connecticut from North Canaan to Stonington (via modern Route 2). Between the New York state line at Salisbury and North Canaan, the road was known as Route 121.

In 1926, most of New England Route 3 became U.S. Route 6. In the 1932 state highway renumbering, New England Route 17 was broken up into two newly assigned routes: modern Route 2 east of Hartford, and part of Route 101 west of Hartford. Route 101 was reconfigured in 1932 from its 1920s alignment to continue west of Phoenixville along former Route 109, then overlapping with US 6 to Hartford. Route 101 then used the western half of former New England Route 17 to North Canaan where it ended. The road from North Canaan to Salisbury was renumbered in 1932 to Route 199 to match the route number in New York at the time. In 1935, US 44 was designated and utilized Route 101 across the states of Connecticut, Rhode Island, and Massachusetts. Route 199 was also incorporated into the new route, connecting with the New York state line.

In the 1940s, US 44 was relocated along a portion of the Wilbur Cross Highway for several years with the former surface alignment becoming US 44A. The change was later reversed. US 6 was also relocated in East Hartford and Manchester to use I-84 and the overlap between US 6 and US 44 is now only between Manchester and Bolton Notch.