Transportation from Marco Polo Airport Venice to Venice Late at Night

Your options are: bus to Piazzale Roma (runs late) and then either take a vaporetto water bus from there to your hotel (check schedules)... or a water taxi from the airport. The water taxi from the airport probably makes the most sense for five unless your hotel is within walking distance of Piazzale Roma. You can check the schedule of the Alilaguna water buses from the airport, but you might be too late, and if it won't get you directly to your hotel anyway (if you still have to take a vaporetto on to your hotel), it might not be much cheaper than taking a taxi.

By the time you actually exit the airport it is probably past midnite
Make sure your hotel has 24 hour desk

We arrive at the Marco Polo Airport in Venice at 10:25 PM.

Where does the flight originate? If from a non Schengen country, you have to go through passport control. This would push your arrival time to the hotel likely well past midnight. Even if coming from a Schengen country getting to a hotel much before midnight is questionable, especially if you have to wait for checked bags.

Does your hotel not have 'how to get here' info on their website?

Does the hotel have check in that late?

For 5 people at that hour I would absolutely take the water taxi. This is the company we used: https://www.motoscafivenezia.com/en/

They typically charge 122 Euros for a private ride. Your 5th person will create an add-on fee of 10 Euros. In addition, an after 10pm ride adds another 10 Euros.

hey hey idenglish
since there are 5 of you and it's late at night, look into the private water taxi and share the cost about 130E, check times available and do a "dummy" booking to see what they offer.
venicelink.com
motoscafivenezia.it
great way to arrive in venice, we have done it 4 times. where are you staying at in venice? they picked us up marco polo airport and took us as close to accomodation/boat stop. your group is only ones on boat with them helping with luggage
let your host/hostess know your arrival time and they will be there to meet you. print a map with directions to your place so driver knows where you are going.
check the alilaguna or vaporetto times/tickets. you will be in charge of luggage, getting in and out, crowded boat possibly, finding way to place in the dark.
depends what your priorities are arriving, cost is so so worth it, no stressing. put money is the "kitty jar" saving for it
europeforvisitors.com/ venice
others will come in and give you other info. good luck and enjoy, one of my favorite places
aloha