The added value of patient-reported outcome measures (PROMs) in addition to standard clinical outcome tools in the assessment of relapsing-remitting multiple sclerosis (RRMS) patients' status is increasingly recognized. PROMs facilitate the detection of hidden aspects of MS and help to integrate the patient's subjective experience of health-related quality of life (HRQoL) status and treatment satisfaction in a holistic way. However, the relationship between PROMs and clinical and cognitive status has been scarcely investigated up to now. To investigate the association of PROMs with physical and cognitive disability in a cohort of RRMS patients at initiation of a new disease-modifying treatment. In this cross-sectional bicenter study, 59 consecutive RRMS patients underwent neurological examination with EDSS assessment, comprehensive cognitive tests (BVMT-R, SDMT, CVLT-II) and a set of self-reported questionnaires. Lesion and brain volumes were analyzed and processed by the automated MSmetrix® software (Icometrix®, Leuven, Belgium). Spearman's correlation coefficient was used to evaluate the association of collected variables. A cross-sectional logistic regression analysis was performed to find baseline correlates of cognitive impairment. Of the 59 RRMS patients (mean age 39 ± 9.8years, 79.7% female, median EDSS 2.0), 33 (56%) had cognitive impairment. While almost all dimensions of health, explored by PROMs, were impacted in the overall sample, no significant difference was observed in patients with and without cognitive impairment. All PROMs were significantly associated with EDSS (R = 0.37-0.55; p < 0.05), except for the psychological component of MSIS-29, BDI and DEX-Q scores. No significant correlation was found between PROMs and cognitive performances. The cross-sectional logistic regression analysis included age, gender (female), education, EDSS, hippocampus and FLAIR lesion volumes as significant predictors of cognitive impairment. The data highlight that PROMs provide valuable information on the well-being of PwMS closely paralleling the extent of MS-related disability, as measured by the EDSS. Additional research should determine the relevance of PROMs as longitudinal outcome measures.