Questions about trains - to pre-book or not?

Karen, In general the advice is NOT to pre-purchase tickets immediatley after an intercontinental flight. Too many variables. Just buy on the day for the next train. It will cost more, but Italian trains are reasonably cheap.
Taxiing, de-planing, walking though the terminal and immigration could take 1 - 1½ hours. Immigration will be the longest delay. Customs takes zero time, just walk thorough the "nothing to declare" door. But, an intercontinental flight could be 1-2 hours late, or 1 hour early, that is the biggest variable.
There should be no trouble getting seats, the trains do not totally fill up, and there is always another train in 30 or 60 minutes. But, if there are 4 of you, you may not get to sit together.

The problem is that the cheap tickets become worthless if you miss your train because of late arrival or a long delay clearing immigration. Right now, I'm seeing the rock bottom prices of 30 EUR per person for the 11:08 direct train to Venice from Fiumicino Airport, but that is only on a Tuesday or Wednesday arrival. The other days are 40 EUR per person or higher. The normal price walking up is about 92 EUR per person.

If you look at the schedule today for Feb, you will only see the 2/day direct trains from Fiumicino, but there are trains at least once per hour from Rome Termini or Tiburtina station. The connecting trains from Fiumicino to Rome are very frequent (every 15 minutes normally). There are separate trains that go to Termini station or Tiburtina station. To Termini is the Leonardo Express, to Tiburtina is the local Regionale that makes several stops along the way and costs less than the Leonardo Ex, but it is not much. The big ticket is the train to Venice.

If you could get 30 EUR tickets now, and would be willing to wait in lovely Fiumicino airport for up to 3 hours, it might be worth the gamble. But if you land on time and breeze through immigration, you'll be looking at each other and thinking, "Gee, if we would have just spent another 60 EUR, we be on our way to Venice right now."

Trains to Roma Tiburtina depart every 15-20 minutes, trains to Roma Termini depart every 30 minutes.

It would be way too stressful for me to buy a day-of-arrival ticket in advance, but if you are a gambler, it could be worth the risk. Throwing away four tickets because of a plane delay would bother me.

Thanks everybody for the replies. This definitely helps. Good to know that trains don't generally fill up too.

I suggest booking a hotel close to Rome Termini for the first night. Relax. Have a good meal. Get over any jet lag. That way you can book your train for the next day and benefit from reduced prices, which will more than make up for the cost of a hotel.

Something else to consider: Stay in Rome for as long as you want. Go to other cities. Fly home from another airport using a multi-destination ticket. Saves the first-day stress. Saves time. Whatever difference in plane fare price (probably small to nil) will be negated by the cost of getting back to Rome. Although cities such as Milan or Bologna have busy airports, you may change planes in another gateway for intercontinental travel. That's still faster and easier than going back to Rome.
But: The multi-city ticket must come from a multi-destination search function. It is not two one-way tickets.

Someone above suggested to book a hotel in Rome the first night.

I would not do that. That would be a waste of time and money. A hotel in Rome will cost you more than 4 discounted tickets at the "Supereconomy" fare (or as much as two full fare "base" tickets). In addition changing hotels is time consuming. You are already planning to stay in Rome at the end of your trip.

Your choice to head to Venice upon landing is, IMO, the right choice. You can rest during the 3h45min train journey.

Regarding pre purchasing discounted tickets, you received great advice above, especially from Zoe. Savings are big, but there are risks involved since planes don't always land on time.

The chance of seats being sold out to Venice in February in any class (including 2nd/standard class) is less than zero percent. It never never happens. To prove this point, check the Trenitalia website tonight when it's morning in Italy. You will see that no trains will be sold out in low season. However only full "base" fare will be available on a same day purchase.

If you were traveling in high tourist season, then some trains could have their second class (standard class) sold out in the early morning trains. In that case you would need to upgrade to the more expensive first (business) class (which never sells out, not even in high season) or wait for a train departing in the late morning (which rarely, if ever, sell out their standard class seats).

If you haven't purchased your flight tickets, you should strongly consider an open jaw ticket into Venice. Probably save money and a whole lot more convenient. You will have no problem getting on the train even if you bought tickets five minutes before departure. Trains rarely sell out and at that time of year you will have plenty of seats. If you can get a super economy ticket on the 11.00 direct I would do it. It is a safe gamble with a 6.40 arrival. There is always a risk that something could go wrong and miss that train but the SE ticket is cheap enough to risk it. With that time interval you should have enough time to fresh up a bit, have a nice breakfast before hitting the train. Once you are inside the train you will sleep.

We never purchase train tickets in advance for the day of arrival. Just too many things can go wrong to cause a delay and then the tickets are just money down the drain. But if you build in several hours of time between airplane arrives and the train departs you might be ok. It just depends on your tolerance for risk and the amount you would lose if you miss the train.

I would not prebook either. The worry about missing the train is one more travel stress you don't deserve. In October, none of the trains we took were full; we always had four seats for the two of us. I found the train fares quite reasonable for the distances. Only prebooked Florence to Rome because our rental owner wanted to know our arrival time.

Take a white taxi from the airport to Termini Station.

I always travel to Italy during "shoulder season" and have never purchased a ticket beforehand and have never experienced a sold out train. I arrive into Zurich off of a Delta flight at 900a.m. I get on the train at the airport and travel down into Italy, enjoying the scenery and resting from the international flight. I usually go as far as Verona and stop there for my first night but, last trip, I stopped at Lake Maggiorie for my first night.

Thank you everybody for all your replies. We are flying in to Italy from New Zealand via Asia, so it'll be a very long flight. Unfortunately the open jaw ticket was not an option (I did try) as we would have wasted more time with connections via other European cities.

After having travelled for a total of about 25 hours plus a 3-hour transit, maybe a first night in Rome to break the journey might sound like a good idea now. I will check out the options and rework my itinerary.

Again, thanks everybody for all your thoughts. God bless.

Thank you everybody for all your replies. We are flying in to Italy from New Zealand via Asia, so it'll be a very long flight. Unfortunately the open jaw ticket was not an option (I did try) as we would have wasted more time with connections via other European cities.

After having travelled for a total of about 25 hours plus a 3-hour transit, maybe a first night in Rome to break the journey might sound like a good idea now. I will check out the options and rework my itinerary.

Again, thanks everybody for all your thoughts. God bless.