Soon after the signing of the Mudros armistice in October 1918, British troops arrived in Istanbul to begin what would become the formal occupation of the city by Allied forces (until 1923). The stated rationale for the occupation was to observe Ottoman Turkish treatment of Christian minorities and guarantee that the Turks would observe the terms of the armistice. British administrative documents illuminate, however, the ways in which occupying forces created infrastructure in Istanbul to maintain postwar geopolitical and territorial control within and beyond the city, for the interests of the British Empire. This infrastructure included the material elements of transportation and communication that facilitated control over the city and brought the British into encounter with diverse Turks. This infrastructure also facilitated Istanbul's material and social interconnections with British imperial nodes such as Malta and Calcutta. This paper builds on recent research that focuses on Istanbulite Turkish experiences of occupation, with an effort to understand Turkish and British experiences of the armistice era in Istanbul as relational and interdependent. I study primary sources from the British National Archives, the Imperial War Museum, and the British Postal Museum and Archive that document the complex processes of dismantling the occupation in 1923. These documents record the challenges involved in closing the post office, removing war equipment and material from warehouses at Tophane and the port at Karaköy, transferring the British ownership of private properties throughout the city, vacating Ottoman state administrative buildings and schools, and providing for the material needs of the many British and Ottoman citizens who worked for the empire but who were being evacuated to Greece, London, or various places in the British Empire. Studying the dismantling of the infrastructure of occupation reveals how embedded the British administration and its individual employees had become in the urban and social environment of the city. Indeed, the people who worked in the administration of empire were themselves influenced by the material and practical experiences of the occupation. This research thus helps scholars consider how the urban environment of the perishing Ottoman capital city played a role in shaping British perceptions and expectations for postwar national futures.