Carnival Miracle sails from Seattle on Thursday, September 17

Smith Cove Cruise Terminal (Pier 91)

Your cruise line's window wins

Most cruise lines assign an arrival window during online check-in — set yours as soon as check-in opens, since the best slots go first. Don't arrive before your window opens: terminals typically hold early arrivals outside, so getting there early buys you nothing. Experienced cruisers most often point to early afternoon, once the first rush has cleared, as the smoothest time to walk in. Follow the check-in instructions your cruise line sends you — they always take priority over general guidance.