Planning a trip for September, 2025. Itinerary so far:

9/7-9/10 Milan
9/10-9/12 Parma
9/12-9/14 ?
9/14-9/17 Stresa, Lake Maggiore
9/18 fly home

Any suggestions for the 2 nights that we have not booked yet? Some ideas are to stay in Bergamo or Lake Como (not sure what town). Open to anything.

I would think it would depend on your interests!
If you haven't seen it, the Michelin Green guide is, IMO, excellent for northern Italy.

A train trip to Bologna would be easy, joaniess. Great food there and easy to visit Ravenna.

We stayed in Belagio on Lake Como and arrived and left by train in Varenna.

You might want read some of the trip reports to get ideas.

Bologna, Verona, Bergamo, Mantova, Pavia.......
You don't need more than 1 day for a somewhat decent visit of each of these towns, bur it's very easy tto do daytrips to other sights from there.

I find it helpful to list a date only once when sharing an itinerary. Listing a date twice makes me think I have more time someplace than I have.

Current Itinerary:
9/7- travel to Milan
9/8- Milan
9/9- Milan
9/10- travel to Parma
9/11- Parma
9/12-travel to ?
9/13- ?
9/14- travel to Stresa, Lake Maggiore
9/15- Stresa
9/16- Stresa
9/17- Stresa
9/18- travel home

Have you been to any of these places previously? For me, rather than change location again, my tendency would be to add the days to locations you have already scheduled. This would give time to go a little more in depth or easy on your schedule, or to add in a nearby day trip. Knowing the day of the week can also be helpful when planning which days might be better to visit a place and which might have closures. Museum and weekend closures might make a difference.

One example:
Su 9/7- travel to Milan
Mo 9/8- Milan
Tu 9/9- Milan
We 9/10- Milan
Th 9/11- travel to Parma
Fr 9/12- Parma
Sa 9/13- Parma
Su 9/14- travel to Stresa, Lake Maggiore
Mo 9/15- Stresa
Tu 9/16- Stress
Tu 9/17- Stresa
We 9/18- travel home

I highly recommend going to Turin - it's an incredibly beautiful city. With many castles and museums. You can easily spend two days there. It's a very quick train ride from Milan.


Torino

You can see my recent TR which included places like Bergamo, Turin and Varenna, if helpful.
Northern Italy May 2024 : Lombardy, Piedmont and Liguria

I agree with ellenem. I would split your extra days between Parma and Stress.

Thanks so much!

That was a typo! I hope your trip involves no stress!