This article explores the potential for just knowledge production in Urban Living Labs (ULLs) by foregrounding epistemic justice. Drawing on autoethnographic and ethnographic methods, it examines how testimonial and hermeneutical injustices shape the formation, implementation, and dissemination phases of EU-funded, research-led ULLs. Findings show that funding structures, academic framings, and dissemination formats constrain the inclusion and recognition of diverse voices, particularly those of citizens. Despite researchers’ efforts to manage power asymmetries, broader societal hierarchies and institutional path dependencies are often reproduced. The study identifies three interrelated strategies researchers use to navigate these challenges: they manage path dependencies, negotiate expectations, and curate knowledge production. These reflect the ethical dilemmas researchers face when balancing co-creation ideals with institutional demands. Conceptualizing ULLs as deliberative spaces highlights their vulnerability to epistemic injustice and illustrate how questions of mandate, power, and responsibility remain under-theorized, calling for a more reflexive and structured approach to ethical practice in ULLs. By foregrounding epistemic justice, this study contributes to critical debates on knowledge production in the new experimental governance spaces that are currently developing in the intersection between planning and innovation contexts, and offers insights for both research and for EU programmes aiming to foster inclusive urban transitions.