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Abstract Technip Energies has recently completed a fit-for-service and life extension project for nearly 200 submarine pipelines with a total length of over 2,000 km in the Gulf of Thailand. One of the main challenges in this project was to accurately determine the remaining life and necessary intervention works for free spans, which are a typical concern for pipeline integrity with respect to local buckling and fatigue capacity. Initial assessments revealed that the conventional free span evaluation method of comparing observed free span lengths with analytically determined allowable lengths would lead to extensive intervention works. Additionally, ROV (Remotely Operated Vehicle) surveys showed a continuous increase in free span lengths due to scouring, and pipeline Inline Inspections (ILI) identified multiple active corrosion defects at span locations. These findings underscored the importance of developing an automated approach to enhance free span assessment accuracy with higher workflow efficiency. The automated approach developed integrates industry-standard design tools with tailored in-house programs to streamline the free span assessment process. The workflow begins with a detailed analysis of pipeline design data, ROV survey and inline inspection data. ROV survey data from multiple inspection campaigns are analyzed to determine free span lengths, gaps, and growth rates, while inline inspection data are used to identify major corrosion defects and their growth. An in-house program is then used to develop a global finite element (FE) model for the entire pipeline – either on a flat seabed with predefined free spans or on a more realistic undulated seabed profile to account for rotated boundary conditions. This FE model accurately captures the on-bottom condition of the free spans, including the effective axial force. Free span growth is either incorporated directly in the global model (through multiple analysis iterations) or its effect is considered separately through a mapping function. For spans affected by corrosion, a separate specialized program develops a localized 3D shell element finite element model featuring local pipe wall thickness reduction from corrosion to determine equivalent pipe stiffness for fatigue analysis and corroded bending moment capacity for local buckling assessment. Outputs extracted from the global FE models serve as inputs to pipeline local buckling assessment and Vortex-Induced-Vibration (VIV) fatigue analysis software for a comprehensive fatigue analysis. This paper presents the developed automated free span assessment methodology together with a case study of a typical free spanning pipeline with internal corrosion. The paper compares various modelling techniques and their effects on fatigue damage and local buckling assessment results. The findings provide valuable insights for the assessment of free spans in corroded pipelines in dynamic seabed environments, enhancing the service life of operating subsea pipelines while substantially reducing unnecessary intervention costs.