Liquefied natural gas (LNG) is expected to become an important part of the UK's energy supply as national hydrocarbon reserves on the continental shelf have begun to dwindle. However, the use of any carbon-based fuel runs counter to the reduction of greenhouse gas emissions (GHG). As a result, an extensive environmental assessment is needed to analyse LNG imports into the UK. Users of this data set should pay close attention to the following methodological advice: The environmental impact assessment for LNG imports should include the entire supply chain, from extraction through to distribution to the final user. It is critical to account for direct, indirect, and avoided emissions when evaluating the life cycle of LNG imports. The functional unit of '7 MJ of natural gas delivered under grid pressure' should be upheld. This data set excludes the usage phase of natural gas. Sensitivity analysis should be conducted considering key parameters such as energy requirements, propulsion fuel, transport distance, tanker volume, and feed gas composition. Limitations of the CML method used in the assessment should be acknowledged, and the data should be interpreted within the technological and temporal boundaries established by the study.