Best options from Sorrento to Rome

You can either take the Cicumsuviana train or the high speed ferry to Naples. From there take a Trenitalia or Italo train to Rome.

Veronica, the easiest way on public transportation is to take the Circumvesuviana train from Sorrento to Napoli Centrale. From Napoli Centrale, you can take either the Trenitalia Freccia fast train or the Italo fast train to Rome.

One other option is the Marozzi bus that runs once a day from Sorrento to the large bus station across the street from the Roma-Tiburtina train station. This run departs Sorrento at 6:00am and arrives in Rome at 09:45am. Bus fare is a lot cheaper than the train.

Thank you very much! ... I don't know where I got the idea from that there was a direct train from Sorrento to Rome, but I guess I was wrong . Do you recommend buying tickets in advance? So thankful for your useful responses!

Hi Veronica. As others have said, you can take the Circumvesuviana train from Sorrento to Napoli Centrale and then a direct train to Rome. I suggest using Italo Treno over Trenitalia if they have a train at the time you need it. The Italo trains are hands down nicer than Trenitalia and it took 1 hour to get to Rome. The Italo trains are new, super clean and very comfortable. Italo uses Roma Tiburtina station as opposed to Termini but since we took a taxi from the station to our hotel, it didn't make a difference for us. It was the same distance from Tiburtina to our hotel as it would have been from Termini. You can definitely pre-book on Italo's web-site (www.italotreno.it) though you probably won't get a discount since you are traveling next week. I would only pre-book if you're sure you'll be able to get to Napoli Centrale on time because you can't change the ticket or get a refund. Have a great trip!

There is a direct bus from Sorrento to Rome, but I've taken the train. Don't let anyone touch your bags in Naplkes train station! With 4 you may want to check car services as the convenience can offset the cost. 4 seems to be the number that makes it worth splitting for me.

The cheapest option (also convenient) for 4 people is to rent a car in Sorrento, drive to Rome, and return it in Rome. Even with a large vehicle it wouldn't cost more than €80 (including no deductible insurance) for the rental plus no more than €40 for gas and freeway tolls.
If none of you knows how to drive, I would also consider a NCC, or Noleggio Con Conducente (car hire with driver). I looked online (search using the words above + Sorrento ) and most require you to contact them via email for quotations, but I've seen some NCC based in Rome that quote from Rome to Sorrento for About €400..
The Marozzi bus would also be good, convenient and cheap. They load the luggage in the belly of the bus and you don't have to worry about it and there are no trains to change.
The train is ok if you don't have a huge amount of luggage to haul along.