But the flight from Malpensa is just going to Zurich, not to the US.

It is a connecting flight. I feel more comfortable with a 2-3 hour window regardless.

Check Swiss' website:
https://www.swiss.com/de/EN/prepare/.../checkin-times

Check-in counters at MXP do not open until 2 hours before departure.
So going to the airport 3 hours before departure would be a waste of time, IMO.

As mentioned above, there is nothing spectacular happening when you check bags to the US via another Schengen airport.
Visitors may be asked if they have ESTA clearance when they travel on the visa waiver scheme. Or get checked if they have the visa, when required.
As a US citizen the staff at bag drop will obviously see that you are good to travel when you show your passport.
This procedure adds approximately 60 seconds to the regular bag drop procedure.

Security check at MXP is same as for any other flights, domestic, intra-Schengen or international.
No passport control until you get to Zurich and transfer to your connecting flight.
Additional security check for flights to the US also in Zurich, not Milan.

Thanks so much. That is very helpful. I am going via the States to Canada. I hope that won’t complicate matters. It ahouldnt though.

Cowboy - confirm what you say about check-in time.

Also remember that although Switzerland is still in the Schengen area it is NOT in the European Union customs area so any tax free purchases have to be declared in Milan and not Zurich!

Well, no.

Customs is cleared at OP's destination, i.e. Canada.
Since OP travels via the US, there could be some issues with taking tax free purchases (or rather: any kind of purchases from abroad) via the US.
The latter is a scenario I'm not familiar with.

But neither in Milan nor in Zurich, anything needs to declared when leaving the EU's custom union towards Zurich and when OP stays airside in Zurich and does not go through Customs in Zurich.

In OP's case, the benefit when shopping at MXP's duty free shops would be that OP can shop there at "non EU travel prices"
Though I would be careful with liquids/spirits/etc. until I knew if those sealed bags from Milan would also be okay at the security checkpoint in the US.

Cowboy - you are absolutely incorrect!

I did NOT refer to customs clearance at destination BUT rather tax free purchases. As Zurich is OUTSIDE of the customs union of the EU anyone wishing to avail themselves of tax-free purchases in Italy either through the recognised programs (which are a bit of a rip-off IMO as they charge generally a 30% handling fee) or directly with the vendor MUST get the necessary stamp at Malpensa which is a simple process. This must be done at Malpensa and NOT Zurich as by then you are already outside of the EU for tax purposes.

I havd the answrr to this question. No worries about tax free pruchases as I am all about the experience and definately will not be shopping. Thanks for all the responses.

nochblad -
I misunderstood your first post.
I thought you were referring to tax free purchases at the airport after security control.
And not the tax free scheme for purchases outside the airport anywhere else in the country.
For which your description is obviously correct.

My husband is always asked at the first check in whether he has ESTA, but I'm not asked, because even my Italian passport says I was born in the USA. As Cowboy confirms, this doesn't add anything to checkin time.