Livestock manure is a significant source of methane and nitrous oxide emissions, posing serious environmental challenges. While conventional management often exacerbates these impacts, thermochemical technologies such as pyrolysis, gasification, and hydrothermal processing offer promising pathways to convert manure into energy, biochar, and other valuable products within a circular bioeconomy. However, these processes can still emit carbon, limiting their environmental benefits. Integrating carbon capture technologies can mitigate these emissions, enabling net-negative outcomes and enhancing overall energy efficiency. This review explores the technical, economic, and environmental aspects of thermochemical manure valorization and emphasizes the transformative potential of coupling these processes with carbon capture. Combustion and co-firing reduce greenhouse gas emissions compared to fossil fuels, but are hindered by manure’s high ash and moisture content. Advanced thermochemical methods such as pyrolysis and gasification yield biochar, bio-oil, and syngas, yet face similar limitations. Hydrothermal processing, especially hydrothermal liquefaction and carbonization, effectively addresses moisture-related challenges and is particularly effective for pig manure. Catalytic gasification further improves conversion efficiency and product quality but remains costly due to expensive catalysts and process complexity. Evidence suggests that integrating carbon capture with thermochemical conversion offers a viable solution for achieving net-negative emissions. However, the widespread deployment of these integrated systems is constrained by high capital costs and infrastructure requirements. Realizing their full potential requires targeted investment, technological innovation, and robust policy support to overcome existing barriers and drive scalable, sustainable implementation.