I consider e/c natural wine shop a hidden treasure in Milan. Inside a building with an "Emergency" (that is actually an ONG) plaque outside, the first thing one might think is that is a hospital. Once passing the wall, there's a cute internal square, with Basilica di Sant'Eustorgio view. You can sit both inside or outside, which a strongly recommend for spring and summer days. A nice place for just passing by to grab a bottle of wine and drink it at home, having a glass of wine (they have many options) or enjoying a relaxed evening.

Nilufar Depot: three storeys of historic and contemporary design, selected by Nina Yashar, one of Milan’s top design dealers. 

Cozy ambient inside, but also with tables on the street, Champagne Socialist is a good place to try natural wines from Europe. You can also go there just to buy a bootle (or more, of course) and drink it at home.

Tiny wine bar and store in Milan's Chinatown area, selling wine by the bottle and by the glass, alongside small plates/snacks. Friendly staff and great selection of wine. Always popular so be prepared to stand!

Cute cafe designed by Wes Anderson at the Prada Foundation. The interior is in the style of a Milanese bar from the 1950s/60s and has a good selection of sandwiches, coffee and alcoholic drinks.