Cartosio

{{Infobox Italian comune

| name = Cartosio

| official_name = Comune di Cartosio

| native_name =

| image_skyline = DSC_2665.jpg

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| image_shield = Cartosio-Coat_of_Arms.png

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| coordinates = {{coord|44|36|N|8|25|E|type:city(782)_region:IT|display=inline,title}}

| coordinates_footnotes =

| region = Piedmont

| province = Alessandria (AL)

| frazioni =

| mayor_party =

| mayor = Mario Morena

| area_footnotes =

| area_total_km2 = 16.7

| population_footnotes = All demographics and other statistics: Italian statistical institute Istat.

| population_total = 734

| population_as_of = 30 November 2019

| pop_density_footnotes =

| population_demonym = Cartosiani

| elevation_footnotes =

| elevation_m = 230

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| postal_code = 15015

| area_code = 0144

| website = {{official website|http://www.comune.cartosio.al.it/}}

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}}

Cartosio is a comune (municipality) in the Province of Alessandria in the Italian region Piedmont, located about {{convert|80|km|mi}} southeast of Turin and about {{convert|40|km|mi}} southwest of Alessandria.

Cartosio borders the following municipalities: Castelletto d'Erro, Cavatore, Malvicino, Melazzo, Montechiaro d'Acqui, Pareto, and Ponzone.