Train connection times

Although it takes a bit longer, using the IC train from Monterosso or Sestri Levante to Milano Centrale, then a Frecce train to Venezia S. Lucia my be more straight forward.

You could also take a later train from Florence to Venice. What time is your train and from where?

Book each leg separately
Leave earlier on the leg to Florence.
The trains run late in Italy 90% of the time I have taken them.` I would not trust twenty minutes to transfer.

The change in Pisa is not a problem but I don’t think I’d be comfortable with only 6 minutes in Florence. The terminal in Firenze has 19 platforms so possible late arrival, disembarking, handling your luggage, finding the platform for your train to Venice and walking from one platform to the next is an awful lot in 6 minutes. There are hourly trains to Venice so I’d take my time, have an espresso and a cornetto and relax between trains.

The platforms are all on one level, and there are only 18 tracks, so it's possible. Have your luggage in hand and perhaps make your way towards the train door as it is pulling into the station. If you have the app, and data, you can see in advance which platform you need for the connecting train. More info on SMN station here: https://www.seat61.com/stations/florence-santa-maria-novella.htm

But the suggestion of just taking an earlier train to Florence or a later one to Venice is a good one.

Although it takes a bit longer, using the IC train from Monterosso or Sestri Levante to Milano Centrale, then a Frecce train to Venezia S. Lucia my be more straight forward.

Great advice from Sam. While 6 minutes should be enough, if you are not familiar with the station it’s challenging. Personally, I’d like 15 minutes in Florence. Here is some info on the train stations in Florence. You can find similar info on the site for other stations. https://www.seat61.com/stations/florence-santa-maria-novella.htm

My personal experience in 14 years of travel to Italy that trains are usually on time. Like the airlines, “on time” can include a few minutes late or early.

Florence has 18 tracks (served at SMN during my year in uniform), or maybe I should say 19, since there is also 1A, which in those years was used for cargo only (I don’t think 17 and 18 are used much either). For technical reasons, the trains from Pisa will arrive on the western tracks (1 to 5 generally, sometime 6), while the trains to the North (like Venice) on the high speed line depart on tracks 8 to 10. I think 6 minutes is cutting it short especially because Regional trains are not always punctual, as they have the lowest priority for the control tower people (yes, there is a control tower at train stations, like for airplanes, which they call “centralina”, here is the one at SMN, in that red building in the photos).

Thank you! These responses are all so helpful!
Based on the posts here, I now realize the 6-minute Florence connection is not a good option for us especially due to our limited experience, lack of familiarity with the Firenze station, and the possibility that the regional train may not be on time. Now leaning towards the option with the Milano connection. Thanks again, everyone!