Australia’s critical minerals sector is central to the country’s decarbonisation agenda, yet its social legitimacy remains highly contested. In Victoria, where proposed and operating mineral sands projects overlap with farmland and environmentally sensitive regions, tensions over social licence to operate (SLO) have become especially acute. This study examines how communities and project proponents perceive SLO in Victoria’s emerging critical minerals sector and what these perceptions reveal about legitimacy in just energy transitions. The study uses a qualitative multiple case study design of five projects across the Wimmera–Mallee and East Gippsland regions of Victoria. Evidence from ten semi-structured interviews with community, government, industry, and advocacy stakeholders was analysed for perceptions of consultation, governance, and project legitimacy. Findings show SLO is understood as a relational, place-based process shaped by trust, institutional credibility and lived experience. The data also signalled four emergent themes: relational legitimacy, cumulative transition pressures, path-dependent engagement, and place- and legacy-based legitimacy. Consultation was frequently regarded as tokenistic, while trust in mining projects was tied to trust in government. Of note, overlapping renewable energy, transmission, and mining developments intensified local fatigue and seeded greater resistance. Historical mining identities in some places supported greater acceptance, whereas agricultural and environmentally sensitive regions saw extraction as incompatible with local values. This paper argues these legitimacy gaps reflect a trust deficit caused by institutionalised procedural consultation, public apathy in critical minerals compounded by the rapid rise of renewables and transmission projects, and perceptions of SLO as a compliance tool, fuelling scepticism toward the broader energy transition agenda. To make concerted progress in advancing legitimate critical minerals mining operations in regional Australia, further attention is required to assess the impact of current SLO practices on Australia’s national transition agenda, investigating actor interactions in decision-making, and cumulative effect assessment of current status and future scenarios.