In 1821, as the Wars of Independence drew to a close, officials of the newly created republic of Gran Colombia passed a national gradual emancipation law. At the center of it was a Free Womb law that declared legally free the children of enslaved women born after the law's promulgation, while bonding these children to their mothers’ masters until the age of 18. Yet, in addition to establishing a term limit on their legalized captivity, the law stipulated conditions for the commerce in Free Womb children, laying the groundwork for what I refer to as the Free Womb trade. This article presents the first detailed exploration of the origins, operations, and limitations of the Free Womb trade in Colombia, particularly at the level of one province: the northwestern Pacific coastal province of Chocó. I argue that the trade created distinctly bounded market geographies of Free Womb children, who were actively, if at times ambiguously, incorporated into Colombia's slave economy. As a general rule, the Free Womb trade placed captive families at the mercy of their masters; yet, as one extraordinary case reveals, the full extent of the local trade's legal power was not entirely secure.