For a Royal Caribbean cruise in 2026, the online check-in window opens as early as 45 days prior to your sailing date. It is highly recommended to complete this process via the Royal Caribbean app as soon as it opens, as this is when you select your Mandatory Arrival Time (also known as a "wellness appointment" or "boarding window"). These windows typically start around 10:30 AM or 11:00 AM and run through the afternoon. The app check-in remains open until 8:00 AM on the morning of your sailing, while the website version closes 48 hours before. It is critical to arrive at the terminal only during your pre-selected window; if you arrive early, you will likely be turned away to prevent terminal overcrowding, and if you arrive late, you will be placed in a standby queue. Royal Caribbean requires all guests to be checked in and at the terminal no later than 90 minutes prior to the ship's scheduled departure time. Arriving any later than this will result in a "no-show" status, and you will not be permitted to board. Your "SetSail Pass" in the app will serve as your digital boarding pass to be scanned by terminal agents upon your arrival.