As of May 2010, Princeton Borough features a total of 126.95 miles (204.31 km) of roadways, with 118.36 miles (190.48 km) maintained by the municipality, 3.93 miles (6.32 km) by Mercer County, and 8.66 miles (13.94 km) by the New Jersey Department of Transportation. Several major roads, including U.S. Route 206, Route 27, and various county routes like 583, 526/571 (commonly known as Washington Road), and 533, traverse the area, ensuring efficient travel within the municipality and beyond.

Princeton is well-connected to larger road networks, with nearby access to U.S. Route 1, Interstate 287, Interstate 295, and the New Jersey Turnpike/Interstate 95. The closest Turnpike exits are Interchange 8A in Monroe Township, Interchange 8 in East Windsor, and Interchange 7A in Robbinsville Township. Notably, several proposed highway projects, including the Somerset Freeway and Route 92, have been canceled over the years, highlighting evolving transportation priorities in the region.

In terms of public transportation, Princeton is approximately equidistant from New York City and Philadelphia, historically linked to both cities by rail. The Princeton Branch rail line connects to Princeton Junction, part of Amtrak's Northeast Corridor. The Princeton train station has undergone multiple relocations, with its latest move in 2013 enhancing accessibility for commuters. The train service to New York, operated by NJ Transit, is generally faster than the route to Philadelphia, which requires a transfer in Trenton. The local train, affectionately known as the "Dinky," connects Princeton and Princeton Junction, facilitating smooth transit.

In addition to rail service, NJ Transit operates bus routes to Trenton (Route 606) and local services (Route 605). Coach USA Suburban Transit offers frequent daily service to midtown New York City on Route 100 and weekday rush-hour service to downtown on Route 600. Local transportation is further supported by FreeB and Tiger Transit bus services provided by Princeton and Princeton University.

Air travel options are available through Princeton Airport, located three miles north of downtown Princeton in Montgomery Township. The closest commercial airport, Trenton-Mercer Airport, is about 15 miles (24 km) away, offering service through Frontier Airlines to various destinations. Additional major airports include Newark Liberty International Airport (39 miles away) and Philadelphia International Airport (52 miles away).

Overall, Princeton's transportation infrastructure reflects a commitment to connectivity and accessibility, facilitating travel for residents and visitors alike.