Reducing Emissions from Deforestation and Forest Degradation (REDD+) mitigation outcomes have emerged as a critical instrument in the international carbon market. Such outcomes are particularly important as activation of the Paris Agreement Article 6 mechanism facilitates cross-border transfers of Internationally Transferred mitigation outcomes (ITMOs) and their integration into Nationally Determined Contributions (NDCs). This study examines REDD+ credit utilization in Compliance Carbon Markets (CCMs) and Voluntary Carbon Markets (VCMs) to develop strategic recommendations for Korea’s REDD+ implementation and ITMOs engagement. The study analyzes credit issuance, retirement, and market interrelations through literature and policy review. A SWOT analysis is performed to identify market-specific strengths and weaknesses, leading to an optimized REDD+ utilization strategy. The findings show that, while CCMs ensure credibility through legal enforceability, their strict certification and high entry barriers hinder accessibility, especially for developing countries. In contrast, VCMs offer flexibility and faster credit issuance but struggle with credibility and enforcement issues. As REDD+ crediting shifts from a Results-Based Payment (RBP) system to ITMO-driven mechanisms, international transactions are increasing. Based on these insights, this study suggests that Korea should enhance policy coherence and REDD+ credit credibility by leveraging CCMs through the SO strategy to strengthen Article 6 linkages and international cooperation. At the same time, the country should employ the WO strategy to expand developing country partnerships and establish tailored support mechanisms. Establishing a robust institutional framework and aligning REDD+ verification with international standards will be crucial for integrating ITMOs into Korea’s NDC strategy. Future research should explore the expansion of cross-border REDD+ credit transactions and develop quantitative analyses for robust policy recommendations.