Purpose: When managing femoral neck fractures, National Institute for Health and Care Excellence guidelines (2023) recommend total hip arthroplasty (THA) for patients who are expected to independently perform activities of daily living (ADLs) beyond two years. These attempt to clarify the indication for THA versus hemiarthroplasty (HA). Frailty assessment tools, such as the Rockwood Frailty Scale (RFS), may provide surgeons a more objective means to assess patient function. The aim of this study is to ascertain whether frailty assessments are predictive of mortality associated with THA thus helping determine arthroplasty suitability. Materials and Methods: Single-center data was collected retrospectively between 2014 and 2020. Three hundred thirty-three cases were eligible for review. For the RFS, Johns Hopkins Frailty Assessment (JHFA) and Nottingham Hip Fracture Score (NHFS), frailty scores were generated and 2-year mortality was calculated for ‘frail’ and ‘non-frail’ patient cohorts. Results: Overall 2-year mortality was 8.4%. Mortality within two postoperative years was 0.8% for RFS <4 compared to 12.7% for scores ≥4. This highlights an approximate 17-times greater mortality risk between these groups (odds ratio [OR] 17.27, 95% confidence interval [CI] 2.32-128.82, P=0.005). For the JHFA, the 2-year mortality rate for ‘frail’ patients was over 6-times greater than those ‘not frail’ (OR 6.91, 95% CI 3.04-15.72, P<0.0001). Positive findings were noted by the NHFS (P=0.054). Conclusion This study demonstrates that following THA for femoral neck fractures, preoperative frailty scores are predictive of 2-year postoperative mortality. Frailty assessments could objectively guide surgical decision making with respect to offering THA versus HA.