A low cruise fare does not always mean the lowest total vacation cost for a family. Newsweek reports that taxes, port fees and gratuities are often excluded from advertised base prices and can add hundreds of dollars per person.

Families also may spend beyond their initial booking on Wi-Fi, drink packages, specialty dining and shore excursions. Some cruise lines include benefits such as Wi-Fi, onboard credit, cabin upgrades or excursions in certain offers, which can make a higher upfront fare a better overall value for travelers who would otherwise buy those extras separately.

According to Newsweek, Carnival and MSC are among the lines commonly viewed as budget-friendly for families. Norwegian and Royal Caribbean can offer midrange value, while Disney may run promotions that improve its value even when its fare is not the lowest available.

“Kids sail free” promotions can reduce a child’s fare, but families should read the terms closely. The offers may apply only to select sailing dates and trip lengths, include blackout dates, require two full-fare adults, and limit eligibility to the third and fourth guests in a cabin. Taxes, fees and gratuities generally still apply.

Colleen McDaniel, editor-in-chief of Cruise Critic, told Newsweek that travelers should evaluate perks they will actually use rather than comparing base fares alone. She also advised families to first narrow their options to ships that fit their needs for food, activities, entertainment and cabin layout, then compare the full cost of each trip.