Getting from Rome to Palermo

It's too bad that the thread from last week on trains to Sicily was deleted. rome2rio.com will give you your transportation options and cost estimates. You can drill down further to the individual carrier's websites for more detail. Personally, I'd fly.

https://www.rome2rio.com/map/Rome/Palermo

Another vote for airplane

Your question is timely. We were supposed to be in Rome today. Following our stay we were flying to Palermo on Alitalia. That said, another vote to fly. We paid $87 each. Enjoy your planning.

The choices are basically flying or a night train. There are day trains as well, but they are not that fast.

I've made that trip and I would also recommend using a budget flight. That will be the most efficient use of your travel time and provide more time for exploring Palermo.

I took that night train in 2015. It was a nightmare. I guess the tracks are not in good condition, because the train jerked back and forth constantly. I got not one wink of sleep, so I slept most of the next day, the result being that I felt jetlagged for quite some time. In the past I have slept well on overnight ferries, but I have no experience with the ferry from Naples (?) to Palermo. I suggest flying. In case you are not aware, there are more flights to Catania than to Palermo. If you are visiting the eastern part of Sicily, flying into Palermo and out of Catania, or vice versa, might be efficient for you.

I flew from Palermo to Rome on Alitalia on my last trip. Easy flight, not too expensive. The only hiccup was on arrival in Rome, our luggage (entire planes) was on a different carousal than listed. Lesson learned for me, look elsewhere!
There is also a bus line, recommended by our Airbnb host, the Prestia e Comande, that was less than 8 Euro as I recall. Many stops in Palermo. The ticket office is outside and to the right. Nice motor coach and we used it both ways.

I have made this trip several times by flying Alitalia. There are many flights each day and it is an easy, inexpensive trip.

Since Rome is not on the coast, the Palermo ferries depart from Civitavecchia.

I know https://www.gnv.it/en , but there may be other companies.

The railway tracks in Calabria squiggle and hairpin over the Apennines, sleeping is impossible.

As many others have suggested in their responses, I would fly.

Thanks to all that replied to my post. I think we will fly if we can ever, as Americans, be admitted to Italy again.