Background: Locally led humanitarian response is increasingly recognised as essential for effective humanitarian aid delivery. Robust Monitoring, Evaluation, and Learning (MEL) systems are central to enabling national non governmental organisations (NNGOs) to generate evidence, support decision making, and ensure program accountability. Strengthening these systems requires a clear understanding of existing gaps and actionable opportunities for improvement. Objective: This study examined the structure and performance of MEL systems within NNGOs responding to the North-East Nigeria armed conflict, identifying gaps and opportunities to strengthen locally led humanitarian action. Method: A qualitative, cross‑sectional design was used, drawing on purposive sampling of MEL focal persons from NNGOs and INGOs. Data were collected using semi structured questionnaire and key informant interviews, then thematically analysed against recognised humanitarian MEL standards and localisation commitments. Results: Results show that most NNGOs are operating below minimum MEL standards. Key weaknesses include overstretched staffing, weak governance and documentation systems, inconsistent use of MEL frameworks, outdated digital tools, and insufficient MEL budgets. These gaps limit timely data collection, analysis, and use, ultimately undermining accountability, adaptive programming, and organisational learning. Conclusion: MEL systems within NNGOs in Northeast Nigeria operate below required standards and remain chronically under‑resourced, significantly limiting their ability to generate and use timely evidence. As a result, these system gaps weaken the effectiveness, accountability, and adaptability of humanitarian responses in the region. Unique Contribution: This study provides empirical insight into MEL readiness among local humanitarian actors and identifies clear opportunities for strengthening organisational systems, thereby contributing directly to ongoing debates on localisation and organisational development. Key Recommendations: Predictable and dedicated MEL financing, along with strong leadership commitment within NNGOs, needs to be strengthened by integrating MEL performance indicators into organisational systems so that MEL becomes more than a compliance requirement. Governance should also be enhanced through the development of MEL policies, frameworks, and tools, supported by donor mentoring and peer‑learning opportunities.