For a short story I plan to write, I was wondering how long it would take individuals to travel from the United Kingdom to America in 1890.
It turns out there was an unofficial award for doing this particular trip the quickest in a passenger liner, so we have pretty good records. Of course a typical passage would be a bit slower than one where a captain was pushing to win the record, but the times can be seen as a close lower bound to how long it would take for a typical trip.
In the 1890's the Blue Riband was held by double-screw steamships. A four-time holder was the SS Majestic, which made her maiden voyage in 1890 from Liverpool to New York in a bit less than six and a half days. That wasn't quite good enough for the record. At the time the City of Paris held the record on a run the same direction between those two cities at a bit under 6 days. (The prize was for average speed in knots, so it doesn't translate perfectly to clock time, but there is a relationship).
Now of course if you weren't paying top dollar on a state-of-the-art cruise liner it would probably be considerably slower, but this should give you a ballpark figure and a good idea of the lower bound for a crossing.