Selecting appropriate LNG tankers is paramount in the maritime sector. Opting for suitable second-hand LNG vessels is a significant and efficient strategy for managing transportation operations effectively and meeting industry standards. Given LNG tanker specifications and shipbuilding capacity, the second-hand LNG tanker market adequately meets maritime industry demands. Thus, there is a strong motivation to evaluate the current second-hand vessel market. However, uncertainties prevail, necessitating decision-makers to employ a resilient and practical methodological framework to address uncertainties and complex decision-making scenarios effectively. This study proposes a decision-making framework integrating the Delphi and Additive Ratio Assessment (ARAS) methods, leveraging interval type-2 fuzzy sets (IT2FSs). This framework resolves real-life challenges associated with selecting second-hand LNG tankers, demonstrating the practicality of the approach. Using IT2FSs, the Delphi method identifies critical criteria influencing second-hand tanker vessel selection. “Cargo carriage capacity" emerged as the most influential criterion, followed by "purchasing costs" and "year of construction." Moreover, "Mediterranean Energy" was deemed the most suitable second-hand LNG tanker among the six alternatives assessed. Thorough sensitivity analysis validated the proposed model and its implications, confirming its validity and applicability. Fresh food supplier selection for global retail chains via bipolar neutrosophic methodology. Display omitted •The current paper presents the IT2F –ARAS approach, which is robust MCDM tool.•It can be applied to solve highly complicated second-hand LNG tanker selection problems.•It has identified criteria for second-hand LNG tanker selection for the first time.•It presents a novel approach, namely IT2F-Delphi, to select the proper criteria.•It presents a flexible decision-making approach for real decision-making problems.