•Even participants with Expanded Disability Status Scale (EDSS) score≤2.5 present functional deficits when assessed with specific functional tests.•Balance was impaired in 48% of people with multiple sclerosis, followed by manual dexterity (29%) and fatigue (24%), but only a few participants showed cognitive impairments.•Only 11% of the sample reported no abnormal score in the 8 scales of the assessment.•Balance disorders and fatigue rather than diminished endurance predicted walking impairment during activities of daily living.•Early specific balance and fatigue assessment is needed in non-disabled people with early multiple sclerosis. Motor and cognitive disorders appear early in the course of multiple sclerosis (MS) and develop gradually over time. To study the frequency and pattern of subtle functional disorders in people with MS (PwMS) with no overt signs of disability in an early phase of the disease and their association with walking impairments in daily activities. In this cross-sectional study, we recruited PwMS with an Expanded Disability Status Scale (EDSS) score≤2.5 and disease duration≤5years. Participants were assessed with functional scales rating walking endurance (6-Min Walk Test), perceived walking ability (Twelve-item Multiple Sclerosis Walking Scale), balance (Fullerton Advanced Balance scale_short), manual dexterity (Nine Hole Peg Test), fatigue (Fatigue Severity Scale), and cognitive impairments (Brief International Cognitive Assessment). About 90% of the 82 PwMS (mean SD EDSS score 1.5 0.7 and disease duration 2.2 1.7 years) showed endurance values below the expected score; almost 30% showed impairment, and for 57%, perceived walking ability score was abnormal. Balance was impaired in 48% of participants, as was manual dexterity (29%) and fatigue (24%), but only a few showed cognitive impairments. Only 11% of PwMS had no abnormal score on the scales used in the assessment. As compared with EDSS score 0 to 1.5, with EDSS score 2 to 2.5, performance was worse for endurance (difference±61.0m, P=0.016), perceived walking ability (−11 points, P=0.002), balance (+1.9 points, P=0.005), manual dexterity (−2.8 s, P=0.004), and fatigue (−1.3 points, P=0.013). Factors that predicted perceived walking ability were balance (B=−1.37, P<0.001) and fatigue (B=5.11, P<0.001) rather than endurance (B=−0.01, P=048). Even PwMS with no clinical disability and classified as having “no problem walking” present walking and other functional deficits when assessed with specific functional tests. The addition of specific tools could better identify subtle motor and cognitive deficits. Finally, the assessment of balance disorders and fatigue is important to understand individuals’ perceived walking impairments in daily activities.