The agricultural sector is responsible for a significant proportion of global anthropogenic methane (CH₄) emissions, with enteric CH₄ produced from ruminant livestock representing approximately 28% of the total. The development of effective mitigation strategies necessitates the accurate and actionable monitoring of CH₄ emissions. However, a considerable research gap remains concerning real-time monitoring techniques capable of supporting on-farm enteric CH₄ mitigation strategies. To bridge this research gap, this study explores the current status of real-time enteric CH₄ emission monitoring techniques and technologies for ruminants. The study achieves this by reviewing key biomarkers and proxies for ruminant emissions, examining established animal-based measurement techniques, exploring emerging technologies, and critically assessing technological limitations and opportunities. By shedding light on this research area, this study aims to assist stakeholders in developing a viable pathway for on-farm emission monitoring, with the hope of facilitating a meaningful reduction in GHG emissions from the livestock sector.