Frankfurt to Mainz help

I wouldn't bother with an ICE ticket. The cities are connected by S-Bahn and regional trains with more trains per hour and more stops to chose from, and it's less expensive than an ICE, too. It's a little slower because of more stops, but only by a few minutes. No need to buy in advance; just get your ticket from an RMV ticket automat at the station before you board.

Don't forget to time stamp (cancel) your tickets.

What are your starting and ending stations?

Thanks! The Frankfurt (Main) HBH and the Mainz Main HBH

The S-Bahn and regional trains leave from FRA's "Regionalbahnhof", one of two stations. So proceed there after your flight to buy your tickets and board. The station name at the DB site is "Frankfurt(M) Flughafen Regionalbf"

The main Mainz station is Mainz Hbf.

The DB site can of course give you connections to other Mainz locations. Where is your hotel for Th night?

The ICEs do run non-stop between Frankfurt Hbf and Mainz Hbf, but those are the only stations they stop at in the two cities. It looks like there is about one train and hour between the two stops; the ICEs take 33 to 40 min.

On the other hand, there are two S8 S-Bahns an hour taking 39 minutes. It cost 19,60€ for a flexible, single, one-way ticket. Round trip for 2 on the ICEs would cost 78,40€.

There are two regional trains an hour, and they take 32 or 41 minutes. There is a little added time for the S-Bahn because you have to go down escalators to the underground station at the Frankfurt Hbf. The same RMV ticket is valid on both the S-Bahns and regional trains and cost 11,55€ each person one-way, but you can buy a group Takeskarte (all day pass, covering any and all your transit by reg. trains, S-Bahns, or buses all day long in the RMV) for 35,10€.

The website for the RMV is at https://www.rmv.de/c/en/homepage.

Sorry, I think I missed the point that your current plans call for you to travel on Thursday from FRA airport to Frankfurt proper... then on Friday morning from Frankfurt proper to Mainz.

It would in fact be far simpler to just catch the direct S-Bahn or regional train on Thursday from FRA to Mainz (25 minutes) and to spend the first night in Mainz.

How (what mode of transit) are you arriving in Frankfurt? Are you staying in Frankfurt overnight? Where?

The long distance train station is being renovated at the airport right now. I wouldn't plan on a catching an ICE train there. It was pretty empty last week when I was there. As in no trains at all and everyone was being sent to the regional station under terminal 1.

Schedules for trains from Frankfurt to Mainz can be found here:
www.rmv.de

You do not have to validate or cancel your ticket for the day on the RMV trains. They come time stamped.

We’re flying into Frankfurt early Thursday morning. Our plan is to drop our bags at the hotel, see the city, and call it an early night. We are staying in a hotel a few blocks away from the main train station- yes, I have since looked into it and realize it is not the best area. It seems like the street our hotel is on is fine and it has great reviews which is why I booked it. Some have pointed out that we could stay Thursday night in Mainz, I might look into whether or not we can change our hotel reservation. I definitely appreciate everyone’s input!

We are staying in a hotel a few blocks away from the main train
station- yes, I have since looked into it and realize it is not the
best area.

IMO it looks worse that it is. My German friends are embarassed by it, but not concerned about their safety during the day or even into the evening.

That said, I would go straight to Mainz. I personally like Frankfurt and often travel through FRA. But with a half day I think you may find Mainz more interesting for a stroll through the city and a visit to the excellent Gutenberg Musem.

I agree, don't stay in Frankfurt, go straight to Mainz. You can get a hotel right on the river if you want (which I like) or stay around the Gutenberg Museum. Either way there's a lot more to see and do there than around the Frankfurt station.

Which hotel is it? Try Motel One by the Römer, so you can be near the new old town, the medieval churches, the river and all of the restaurants.
Frankfurt is a beautiful city to walk around it too.

Frankfurt is a beautiful city to walk around it too.

Yes it is. I enjoy both Frankfurt and Mainz when I visit Germany. Either is worth your half day or more.