Here are the documents and costs to keep in mind when planning a cruise

As I made plans this summer to take a cruise, I worked my way through my pre-travel checklist. I booked my flights, researched ground transportation options and selected a hotel for the night before boarding.

But I had yet to tick one important box: renewing my expired passport.

I had not traveled internationally since the pandemic began and needed a deadline to motivate me, so shortly before my sailing from the Netherlands to New York, I filled out the application, paid the fees, and did a quick photo shoot at my local Walgreens.

Passports are just one of the documents travelers may need when taking a cruise, which can add to the overall cost of a trip. Here's what travelers should have on hand and what costs they might encounter before and during their trip:

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What documents will travelers need to board a cruise?

The U.S. State Department recommends cruise passengers sailing from America have a passport.

U.S. citizens booked on closed-loop cruises – those that start and end at the same U.S. port – can enter the country with a government-issued photo ID and birth certificate instead, but the State Department encourages having a passport "in case of an emergency, such as an unexpected medical air evacuation or the ship docking at an alternate port," according to its website. Cruise lines may also require it.

Denise Jewell, owner of Opulence Travel Agency, also recommends having a passport, even on closed-loop cruises, in case you don't make it back to the ship in time during a stop.

"It'll be much easier to deal with the locals if you have a passport as opposed to a birth certificate," Jewell said.

If travelers need to apply for or renew a passport, "the sooner you get started the better," said Danny Genung, CEO of travel agency Harr Travel. He suggested beginning that process as soon as you book your trip, even if it's a year in advance.

"This is one of the big pain points and stress points of travel if you wait too long," Genung said.

Even travelers who have procrastinated, though, may not be out of luck. I mailed my passport renewal application on Sept. 7 and paid about $208 in fees overall, including expedited service. I received my new passport on Oct. 3, about two weeks before my trip.

What costs will travelers encounter while taking a cruise?

Many costs associated with a cruise are included in the fare travelers pay when they book. "I think one of the things I would point out is, spending money on a cruise ship is a choice," said Genung, noting that he has been on many cruises and spent nothing additional except on gratuities. However, with mainstream cruise lines, there are generally some key expenses to keep in mind (on luxury lines, many of these costs are likely to be included in the fare).

Taxes, fees and port expenses: In addition to the fare, travelers must pay taxes, fees and port expenses, said Brigitte Feinberg, a travel adviser and independent affiliate of Avenue Two Travel. Those can vary based on the specifics of your trip.

► Gratuities: On mainstream lines such as Royal Caribbean International, Feinberg said, gratuities are automatically added to travelers' bills on a per person, per day basis.

Those prices can vary. Royal Caribbean charges $16 per guest each day staying in non-suite staterooms, and $18.50 for those in suites, while Carnival Cruise Line applies a $14.50 daily charge per passenger for non-suite rooms, and $16.50 for guests in suites, according to their websites.

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Guests can prepay those gratuities, so they "don't have to worry about that bill at the end of the cruise," Feinberg said, or pay them as part of the final bill. Passengers can also adjust the gratuities up or down, though Feinberg does not recommend the latter.

She added that some guests also bring cash to tip crew members directly who "went above and beyond" during the trip.

► Some food and drinks: While much of the food is included on mainstream lines, some restaurants and items may cost extra.

On my October Holland America Line cruise, I visited specialty restaurants with prices ranging from $19 to $49 per person, plus an 18% gratuity.

Lines such as Carnival and Norwegian Cruise Line also include basic drinks like iced tea and regular coffee while charging for others. Genung said, "in a lot of cases there's good value" in pre-purchasing specialty dining or beverage packages.

► Shore excursions: On mainstream cruise lines, Feinberg said, excursions are not included either. "Yes, the room's only $300 for a week, but by the time you're all said and done you're going to be spending a lot more than that," she said.

She said excursions can run from $50 to hundreds of dollars per person.

Most cruise lines have promotional sales on excursions and other packages before the cruise, Genung said, which can offer "significant savings," particularly for families traveling together.

"I have two little kiddos myself, and it's a lot more expensive to travel than when it was just my wife and I," he said. "So, you know, when you multiply an unexpected cost times four, or five or six, it gets pretty exponential."

► Wi-Fi: Many cruise lines charge extra for Wi-Fi, but the price may depend on your needs.

Norwegian Cruise Line, for instance, sells both basic and premium options for one, two, and four devices, starting at $25.50 per day if guests purchase online and about $30 per day if they purchase on board, according to its website. The line also sells a 250-minute option.

Genung noted that it is almost always cheaper to purchase the internet prior to boarding than it is after getting on the ship.

► Laundry: Depending on the length of the sailing, travelers may run out of clean clothes as I did on my October transatlantic cruise.

Like many mainstream lines, Holland America offered laundry services with several options, to choose from. I picked the Laundry By the Bag package, which cost $30 for as many clothes as I could fit in a bag the line placed in my stateroom closet.

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There was also an Unlimited Pressing package for $75 and an Unlimited Laundry option for $135, including pressing, both for the duration of the sailing, according to an info sheet in my stateroom.

Feinberg noted that some cruise lines also have laundry rooms where guests can wash and dry their own clothes, such as Carnival, which charges $3.50 for each washer load, and $3.50 per dryer load, according to its website.

This article originally appeared on USA TODAY: Cruise documents and costs: Here's what to know