This paper examines everyday practices of self-construction and connection, negotiation, and self-disconnection of, and from, formal and informal water infrastructure and services in three global cities – São Paulo, Dhaka, and Cairo. While each city has distinct histories and geographies, we show via detailed qualitative fieldwork in six low- and high-income neighbourhoods how residents face ongoing struggles to access quality, affordable, and sustainable water supply. We make two key contributions to the existing debate on urban water insecurity. First, we highlight that while residents continue to pursue water formalisation as a pathway towards neighbourhood regularisation and broader citizenship entitlements, they do not abandon the hybrid systems of infrastructure and provisioning they use to access water. Instead, these hybrid material, social, and political practices of self-connection and contestation of water services are the cornerstone of negotiating water in/security in everyday urban life for both high- and low-income groups. Second, we focus beyond the formalisation of water supply to highlight how residents maintain, repair, and/or disconnect from water infrastructure and services. We introduce the underexplored practice of 'self-disconnection' as a way in which residents respond to water insecurity in state or community systems, challenging notions of a linear, singular network ideal. The paper concludes by synthesising the diverse ways in which residents respond to water insecurity in their daily lives, across three distinct geographical contexts.