Cosio Valtellino

{{Infobox Italian comune

| name = Cosio Valtellino

| official_name = Comune di Cosio Valtellino

| native_name ={{native name|lmo|Cös}}

| image_skyline = Cosio - panoramio.jpg

| imagesize =

| image_alt =

| image_caption = View of Cosio from above

| image_shield = Cosio_Valtellino-Stemma.gif

| shield_size = 80px

| image_map =

| map_alt =

| map_caption =

| pushpin_label_position =

| pushpin_map_alt =

| coordinates = {{coord|46|8|N|9|32|E|type:city(5,205)_region:IT|display=inline}}

| coordinates_footnotes =

| region = Lombardy

| province = Sondrio (SO)

| frazioni = Cosio Stazione, Mellarolo, Piagno, Regoledo, Sacco

| mayor_party =

| mayor = Alan Vaninetti

| area_footnotes =

| area_total_km2 = 23.9

| population_footnotes =

| population_total = 5413

| population_as_of = 31 August 2010Data from Istat

| pop_density_footnotes =

| population_demonym = Cosiesi

| elevation_footnotes =

| elevation_m = 231

| twin1 =

| twin1_country =

|istat=| saint =

| day =

| postal_code = 23013

| area_code = 0342

| website = {{official website|URL=http://www.comune.cosiovaltellino.so.it/mainPortal/index.php?option=com_content&task=view&id=247&Itemid=318}}

| footnotes =

}}

Cosio Valtellino is a comune (municipality) in the Province of Sondrio in the Italian region Lombardy, located about {{convert|80|km|mi}} northeast of Milan and about {{convert|25|km|mi}} west of Sondrio.

Cosio Valtellino borders the following municipalities: Bema, Cercino, Mantello, Morbegno, Rasura, Rogolo, Traona.

The principal seat of Galbusera (confectionery company) resides in Cosio.