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Abstract Plug and Abandonment (P&A) operations represent a critical phase in the life cycle of oil and gas wells, ensuring long‑term environmental protection and regulatory compliance. In the Gulf of Thailand, where stacked reservoirs and high‑inclination wellbores are common, P&A practices must also enable efficient slot recovery to sustain field development. Slot recovery has emerged as a strategic priority, allowing operators to reuse existing platform slots for infill drilling while minimising capital expenditure on new infrastructure. However, conventional abandonment practices—such as full completion retrieval, multiple cement plug placements in high‑inclination sections, and online well killing—have historically imposed significant time, cost, and safety burdens. This paper presents a structured programme of slot recovery improvements implemented across four mature offshore fields in the Gulf of Thailand between 2021 and 2025. Key initiatives included the adoption of offline well‑killing operations, leaving ESPs in hole, application of the Minimum Safe Abandonment Depth (MSAD) methodology, and optimisation of bridge plug deployment methods. Each initiative was subjected to rigorous cost–benefit analysis and risk assessment, ensuring operational feasibility and economic viability. Performance was monitored over a five‑year period, with slot recovery duration selected as the primary metric due to the similarity of well configurations across the dataset. Results demonstrate a progressive improvement in efficiency, with recovery times achieving 43% improvement in 2025. The time savings translated into cumulative cost reductions of approximately USD 29 million in the period, based on average drilling spread costs. Among the initiatives, MSAD application delivered the most transformative impact by repositioning cement barriers into more reliable intervals, thereby reducing non‑productive time associated with failed plug verification. Additional gains were achieved through offline well‑killing, ESP retention, and wireline bridge plug deployment. Beyond financial outcomes, the programme yielded qualitative benefits including reduced waste generation, lowered greenhouse gas emissions from decreased rig time, and improved personnel safety through reduced exposure hours. Limitations were observed in wells with rapid inclination build, where wireline operations were not feasible for cutting tubing and leaving ESP in hole, and in certain infill wells where offline well‑killing could not be scheduled. These constraints highlight the importance of adaptive planning and continuous improvement to sustain efficiency gains. Overall, the study confirms that slot recovery improvements are both technically feasible and strategically valuable, offering a scalable methodology that can be adapted to diverse operational contexts worldwide. By integrating operational rigor, financial discipline, and sustainability framing, the programme demonstrates how innovation in P&A can advance efficiency, safety, and environmental stewardship in offshore development.