What do you call a Marine Captain? (serious)?

Either - Captain or Sir

All the other answers were correct ,IF you are a subordinate to said CAPTAIN ,now the fact that you are asking tells me you are NOT a subordinate YET-you might be thinking about it (Platoon leader training in college or an enlistment,both fine choices) but the BIGGEST clue and one I am surprised any of the afore mentioned answers LET YOU GET AWAY WITH ,is the "HEY,..." part of your question ,I was never a Marine but even in the BOY SCOUTS you DO NOT say HEY to a superior-LOL ! If you are not a subordinate and/or you are NOT in the uniformed service of ANY soverign nation he is just "FIRST NAME HERE" remember he is a young educated professional who gets that stuff all day -I am in retail sales in Lakewood Wa. (McCHORD AFB is 1 mile east and FT. Lewis is 3 miles south) and service e-1 to 0-8 (Calvin Waller and Norman SChwartzkoph both had thier car serviced here years ago) The rule of thumb I use for my customers is old retirees LOVE the rank thing ,active 0-6 and above like it too but 05 and below especially younger ones like informal unless a lower enlisted is in line or at the counter .hope this helps

You better call him/her "Sir or mam" or the "Captain" may put you in the brig for insubordination and disrespect to a Commissioned Officer and then you are subject to Courts Martial.

A marine is a small can of "Whoop A**" in a brown uniform.

Captain blah blah blah

You had a nasty adventure yet do not decide each and each of the individuals contained in the protection rigidity with the help of that adventure. I have had the sturdy fortune to understand fairly some human beings contained in the protection rigidity and maximum folk of them were no longer like the guy who you encountered. certain the Marines are proud as they might want to be,they went with the help of a confusing application to earn the identify human beings Marine. I have encountered an identical form of those who you describe in civilian existence so it isn't unavoidably their protection rigidity preparation that led to the problem ,yet might want to or not this is the way that they were delivered up.

Captain (last name) Sir/Mam

SIR!!!!

Please Support Our Troops and Civilian Contractors

Sir

you call him sir, no seriously you call him Captain (last name)

USMC 1973-1977 once a marine always a marine

Captain [last name].

It's not necessary to say his branch of service.