How long do US Navy ships stay at foreign ports ?

The usual port visit in a "liberty port" is 5 days.

While deployed the crew will normally be in 4 section duty. That means that each day 1/4 of the crew has the duty and must stay onboard the full 24 hours.

In some ports you are free to do what you want until your duty day rolls around. In others you must be back by a certain time at night. Normally the night return times are staggered.... lowest ranking back at midnight and perhaps senior enlisted and officers back at 2 am.

Each morning at about 8am the off-going and on-coming duty sections will muster. Once the on-coming duty section takes over the off-going section will be relieved and liberty call will be announced for them.

Some ports are "working ports." (Yokosuka, Singapore, Dubai, Bahrain, etc...) These are usually ports where there's a ship yard, repair ship or repair facility. In working ports everyone works until liberty call at about 4pm. The duty section stays onboard.

Each port visit varies, some are just a couple days, others about a week - usual average is 5 days give or take.
Each department sets there own "duty" schedule - talk to your Chief and see if there is a plan set yet for the deployement - although not leaving for another month, might not have a plan yet! Those that are delinquent or not qualified will affect your "shore liberty", get your buddies together and be ready to stand watch as needed so everyone can enjoy and have a beneficial duty rotation!

DO NOT ANSWER THIS QUESTION. THINK OPSEC!

Methods and procedures should be internal and not announced.

Based on my own experience in the Navy, I will attempt to answer your question. Time at sea varies from a few days to a few months, based on the mission. For instance, a carrier based in San Diego may go out for only a few days for carrier quals. On the other hand, a ship may go out for several months (5 or 6) if they are being assigned as part of a fleet. Example: The US keeps a battalion of Marines on board troop ships in the Mediterranean on stand-by status in case an early response is needed for a hot situation in that area. They routinely stay for five months and as they leave the Med through the strait of Gibraltar, another battalion aboard troop ships is entering the Med. An American often makes a port of call visit to various cities in countries that we are friendly with. In the Med, they often include Naples, Catania, Sicily, Livorno, Italy, Athens, Greece, Cannes, France, or in Spain - Barcelona, Valencia, Malaga, etc. You are usually granted "port & starboard" liberty* in those ports and, just like being at home, you return to your ship at the expiration of your liberty. * Since only 50% of the ships crew are allowed to leave the ship on liberty in a foreign port, you get to go only every other day. I enjoyed seeing all those places and hope someday to maybe return there with my wife for a visit. If you have specific questions or just want more info then email me.

Yes I agree with Jon T so think the question carefully.