Belfast to Foynes Sea Distance Calculator

Calculate the exact nautical distance from Belfast, United Kingdom to Foynes, Ireland. Plan your maritime journey with our professional route calculator.

Distance
374.7 nm
nautical miles
Under Sail
3.1 days
at 5 knots
Under Power
37 hours
at 10 knots
Best Time
May-September
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

Loading map...

Distance: 374.7 nautical miles
🧮 Open Interactive Calculator

This map shows the direct sea route from Belfast to Foynes. 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 126% longer than the 166 nm direct line, its heading turning from northeast to east. It is an international crossing between two countries.

Sea distance
374.7 nm (693.9 km)
Direct line
165.9 nm126% longer
Great-circle bearing
225° (southwest)
Geographic extent
2.9° × 5.1°
Crossing
Cross-border · Same region
From
Belfast (United Kingdom) 54.6167, -5.9000
To
Foynes (Ireland) 52.6167, -9.1167
Route basis
Sea-lane route
Passage timeEstimated passage time by cruising speed
Cruising speedDuration
5 kn3.1 days
8 kn47 hours
10 kn37 hours
12 kn31 hours

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 Belfast to Foynes Route

A medium ocean international sea route between Belfast and Foynes, this passage connecting two major commercial ports in the Northern Europe region demands attention to tidal streams and seasonal ice in the higher latitudes.

The corridor within the same maritime region joins Belfast, United Kingdom to Foynes, Ireland.

Navigation Tips

  • •Plan this medium ocean international leg in the Northern Europe region with attention to tidal streams and seasonal ice in the higher latitudes.
  • •Provisioning for this medium ocean passage in Northern Europe should account for regional supply networks.
  • •Allow time for entry formalities on this international leg within the same maritime region.
  • •Adapt safety equipment to Northern Europe conditions for this medium ocean crossing.
  • •For a international crossing within the same maritime region, ensure clearance papers and visas are in order before departure.

Frequently Asked Questions

How far is it from Belfast to Foynes by sea?

This is a medium ocean sea passage of about 374.7 nautical miles between Belfast and Foynes in Northern Europe.

How long does it take to sail from Belfast to Foynes?

Average voyage time on this medium ocean within the same maritime region leg of 374.7 nautical miles is 1.6 days – 3.1 days.

What's the best time to sail from Belfast to Foynes?

Aim for May-September for the calmest passage in Northern Europe; off-peak periods bring tidal streams and seasonal ice in the higher latitudes.

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.

Plan another route with our Sea Distance CalculatorNavigation Guide