Boston to Montreal Sea Distance Calculator

Calculate the exact nautical distance from Boston, United States to Montreal, Canada. Plan your maritime journey with our professional route calculator.

Distance
1378.8 nm
nautical miles
Under Sail
11.5 days
at 5 knots
Under Power
5.7 days
at 10 knots
Best Time
Varies by area
Typical Sailing Season

Distance follows a sea-lane route. Sailing times are estimates at fixed cruising speeds and vary with vessel, weather, and currents.

Interactive Route Map

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Distance: 1378.8 nautical miles
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This map shows the direct sea route from Boston to Montreal. The actual sailing path may vary based on weather conditions and navigation requirements.

Passage details

This is a markedly indirect coastal passage: the navigable route runs 534% longer than the 218 nm direct line, its heading turning from east to south-southwest. It is an international crossing between two countries.

Sea distance
1378.8 nm (2553.5 km)
Direct line
217.6 nm534% longer
Great-circle bearing
331° (north-northwest)
Geographic extent
7.9° × 14.3°
Crossing
Cross-border · Same region
From
Boston (United States) 42.3601, -71.0589
To
Montreal (Canada) 45.5017, -73.5673
Route basis
Sea-lane route
Passage timeEstimated passage time by cruising speed
Cruising speedDuration
5 kn11.5 days
8 kn7.2 days
10 kn5.7 days
12 kn4.8 days

Distance follows a sea-lane route generated from marine traffic lanes; passage times are computed at fixed cruising speeds.

Read the methodology — How we calculate sea distances

Last reviewed 2026-06-17

About Boston to Montreal Route

A long open-water international sea route between Boston and Montreal, this passage connecting two major commercial ports in the North America region demands attention to frontal systems and rapid pressure changes in the colder months, varying by coast.

The corridor within the same maritime region joins Boston, United States to Montreal, Canada.

Navigation Tips

  • •Plan this long open-water international leg in the North America region with attention to frontal systems and rapid pressure changes in the colder months, varying by coast.
  • •Provisioning for this long open-water passage in North America should account for regional supply networks.
  • •Allow time for entry formalities on this international leg within the same maritime region.
  • •Adapt safety equipment to North America conditions for this long open-water crossing.
  • •For a international crossing within the same maritime region, ensure clearance papers and visas are in order before departure.

Suggested Stops

On a long 1378.8 nm passage from Boston to Montreal, these ports make convenient places to break the journey, refuel, and rest.

  1. Sonora (Canada) · ≈483.6 nm in — View port details
  2. Cap Des Mechins (Canada) · ≈1024 nm in — View port details

Frequently Asked Questions

How far is it from Boston to Montreal by sea?

This is a long open-water sea passage of about 1378.8 nautical miles between Boston and Montreal in North America.

How long does it take to sail from Boston to Montreal?

Average voyage time on this long open-water within the same maritime region leg of 1378.8 nautical miles is 5.7 days – 11.5 days.

What's the best time to sail from Boston to Montreal?

Conditions on this route vary by area and season, so there is no single best time that applies along its whole length. Always check current weather forecasts and sea conditions before departure.

Plan Your Perfect Maritime Journey

Use our advanced calculator above to customize your route, add waypoints, calculate fuel costs, and share your journey plan with crew members.

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