A merchant seaman is usually gone for weeks to months , not a fixed amount of time. A common range is about 4 to 6 months on board , followed by time off that can be around 2 to 3 months , but contracts vary a lot by company, rank, and ship type.

What it depends on

  • Offshore vessels often use rotations like 6 weeks on / 6 weeks off , or similar schedules.
  • Deep-sea merchant ships commonly keep crews away for 3 to 6 months at a time.
  • Junior crew may have longer contracts, while senior officers sometimes get more choice over the schedule.
  • Some seafarers are effectively away for 6 to 9 months total each year when you count work time and travel.

Simple example

If someone signs a 4-month contract on a tanker, they may spend those 4 months living and working on the ship, then come home for a period of leave before the next assignment. In another job, especially offshore, they might do 6 weeks away and 6 weeks at home instead.

Bottom line

There isn’t one standard answer. For many merchant seamen, being “gone away” means a few weeks to several months , with 3 to 6 months being a very common pattern.