Royal Caribbean recently raised a fee that some cruise passengers already find shocking

Bad news, Royal Caribbean fans: Now you’re going to pay more to go on a cruise.

The world’s largest travel company this week began notifying customers that an automatic service charge added to passengers’ bills will rise to $21 per person per day.

In emails sent to passengers booked on future trips, the line said the daily gratuity charge, which costs money, will jump to $18.50 per person per day on Nov. 1 for those occupying multiple cabins. Passengers in suites will pay $21 per person per day.

The rates are about 3% higher than Royal Caribbean’s current service charges of $18 for standard cabins and $20.50 for staterooms.

Although relatively small on average, Royal Caribbean’s debt service charge increase is the second in just under a year in a row and brings the cumulative one-year increase to nearly 14%. This time last year, Royal Caribbean was charging just $16 in service charges to passengers in most cabins.

With this increase, a family of four in standard cabin will pay more than $500 in incidentals on a seven-night cruise – one of the highest taxes in the business. Among other major lines, Carnival Cruise Line, MSC Cruises, Princess Cruises and Holland America are adding from $13.50 to $16 per person per day in service charges to the bills of passengers in most cabins.

Celebrity Cruises adds a tax of $18 per person per day to the reduced amount of passenger credits, respectively.

Related: TPG’s ultimate guide to cruise gratuity costs and tips

Royal Caribbean’s premium has risen a remarkable 54% since the start of 2015, when it was just $12. The line has raised rates five times since then.

The 54% increase in Royal Caribbean’s premiums since the beginning of 2015 is about 19% greater than the US inflation rate over the same period.

Inflation in the US since the beginning of 2015 has run at an increasing rate of 35%, according to the US Department of Labor, as measured by the Consumer Price Index for All Urban Consumers.

Most major cruise lines such as Royal Caribbean, Carnival and MSC Cruises automatically add some type of service or credit fee to passengers’ bills. Passengers often choose to prepay service fees when booking or have them added to their cruise fare, which is paid at the end of each cruise.

That said, the total number of pay-for-service lines has been decreasing over the years. Many small and large fleet operators have been rolling these costs into their base costs.

Lines now offering fares include Azamara, Ponant, Explora Journeys, Crystal, Regent Seven Seas Cruises, Scenic Luxury Cruises & Tours, Seabourn, SeaDream Yacht Club, -Silversea Cruises and Virgin Voyages.

Along those lines, the service charge and credit fees are seen as an easy way to cash out on ships – something that used to be the norm.

Cruise lines with such prices usually raise their prices every year or two.

Royal Caribbean has told customers with existing cruise reservations that they can lock in current, lower revenue rates by prepaying fees before Nov. 1.

Note that, in some cases, passengers who are dissatisfied with the service they receive on Royal Caribbean ships can adjust the amount of daily allowance posted to their accounts while on board by visiting the Guest Services desk, depending on the line.

Adjustments are only allowed if available funds are charged to internal accounts at the time of the cruise. Passengers who pay in advance cannot adjust the amount they paid during the ride.

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