Purpose: Assessment of frailty is a key method to identify older people in need of holistic care. However, agreement between different frailty instrument varies. Thus, groups classified as frail by different instruments are not completely overlapping. This study evaluated differences in sociodemographic factors, cognition, functional status, and quality of life between older persons with multimorbidity who were discordantly classified by five different frailty instruments, with focus on the Clinical Frailty Scale (CFS) and Fried's Frailty Phenotype (FP). Participants and Methods: This was a cross-sectional study in a community-dwelling setting. Inclusion criteria were as follows: greater than or equal to75 years old, greater than or equal to3 visits to the emergency department the past 18 months, and greater than or equal to3 diagnoses according to ICD-10. 450 participants were included. Frailty was assessed by CFS, FP, Short Physical Performance Battery (SPPB), Grip Strength and Walking Speed. Results: 385 participants had data on all frailty instruments. Prevalence of frailty ranged from 34% (CFS) to 75% (SPPB). Nine percent of participants were non-frail by all instruments, 20% were frail by all instruments and 71% had discordant frailty classifications. Those who were frail according to CFS but not by the other instruments had lower cognition and functional status. Those who were frail according to FP but not CFS were, to a larger extent, women, lived alone, had higher cognitive ability and functional status. Conclusion: The CFS might not identify physically frail women in older community-dwelling people with multimorbidity. They could thus be at risk of not be given the attention their frail condition need. Keywords: geriatrics, frailty phenotype, clinical frailty scale, outpatient assessment