<p>With growing emphasis on sustainability, companies are shifting from prioritizing cheap labor and high production volumes to focusing on sustainable manufacturing and localized supply chains. This study examines how the sourcing location decision of a Finnish manufacturer affects the carbon footprint of an iron sand-cast component. A questionnaire was used to collect data on material (new and recycled metals and sand) and energy (electricity and heating) consumption for the annual production of real components from foundries in Finland, Germany, the Czech Republic, and China. The consumption data, or activity data, were multiplied by their respective emission factors to calculate CO₂-equivalent emissions per kilogram of the component. Domestic sourcing in Finland produced the lowest emissions, while sourcing in China triples the emissions when including transportation and is more than double when excluding transportation. This highlights significant regional disparities in pig iron and energy usage. The foundry emissions in Finland and Germany were, on average, the same, as heating in the former compensated for the higher electricity emissions in the latter. These findings encourage manufacturers to focus not only on distance but also on the resource consumption of their suppliers.</p> Graphical Abstract <p></p>