Significant coastal vulnerability (CV) in the United Kingdom (UK) endangers the population and the infrastructure and distorts the national economy, yet present and proposed literature only quotes previous circumstances that failed to deliver factual fiscal assessment. The current estimate models for coastal vulnerability are useful for decision-making in some magnitudes, but coastal vulnerability models need to be extended to comprise a wider choice of economic effects. These are real problems that need to be addressed for an estimation of fiscal coastal vulnerability with novel models of science and economics to limit destruction costs or spend with greater resilience. To address the current research gap, this study appraised coastal vulnerability by establishing an innovative model: a Fiscal Coastal Vulnerability Index (FCVI) with fiscal parameters by 2 Path analysis (2 PA). It identifies the coastal vulnerability hotspots in Path One (P1) and develops an FCVI and GIS maps in Path Two (P2). Primary results revealed that 11 sites across the UK (seven in England, three in Wales, and one in Scotland) were identified as fiscally vulnerable coastal areas. Identified sites currently contain £22.36 billion worth of coastal vulnerability, and >100,000 people are at high risk of flooding, erosion, storm surge, and high winds. The Fiscal Coastal Vulnerability Index can be adapted depending on kind of coastal environment and used as a planning tool to establish economic susceptibility. This work explains that the methodological framework can be adjusted for any suitable coastal sites at global or regional scales, and can be used to vindicate in-depth studies for coastal defences and budget.