Abstract Background/Aims Emerging adulthood is a unique developmental period between late adolescence and establishment of personal and social identity associated with adulthood. Emerging adult populations may have distinctive experiences of adult healthcare and their needs may differ from those of older healthcare users. Little is known about the patterns of presentation, experiences of care or disease outcomes of emerging adults in adult rheumatology settings. We used the National Early Inflammatory Arthritis Audit (NEIAA) to describe differences between emerging and older adult patients diagnosed with early inflammatory arthritis (EIA). Methods NEIAA is an observational cohort design study assessing care against National Institute for Health and Clinical Excellence quality metrics. Adults in England and Wales with a confirmed new diagnosis of inflammatory arthritis between May 2018 and April 2022 were grouped into two categories: emerging adults (16-24 years) and older patients (≥25 years). Patient characteristics, disease phenotype (including oligo- or polyarticular presentation) and initial treatment strategy were described. Results A total of 20,472 patients were included. 571 (2.8%) diagnosed with EIA were emerging adults (EA); this group had higher proportions of females (71.8%). Compared to older patients, EA patients were less likely to ever smoke (44.1% vs 69.5%) and had fewer comorbidities. EA patients were more likely to have oligoarticular symptoms (<5 tender and swollen joints; 53% vs 37%). Symptom duration prior to diagnosis was longer for EA patients (46% describing symptom duration >6 months vs 37%). Median Disease Activity Score/DAS28 at presentation was lower (4.2 vs 4.7). There were no differences in symptom burden as measured by the mean musculoskeletal health questionnaire (25 vs 24). EA patients completed fewer patient reported outcomes (33% vs 39%), but were more likely to complete all forms (20% vs 17%). Disease modifying anti-rheumatic drugs treatment strategies appeared similar, although more EA patients did not start medications by three months (26% vs 19%). Fewer EA patients received steroids (56% vs 71%).There were no significant differences between groups in patient numbers referred within three days of symptom onset from primary care or reviewed within three weeks with treatment initiation within six weeks in rheumatology care. More of the EA group were in employment at diagnosis. The EA population reported higher impairment at work (Work Productivity and Activity Index overall score 38% vs 30%, driven by difference in presenteeism). Conclusion Low proportion of EA patients in this EIA population raises concern that the study is not capturing a representative sample of this younger and developmentally distinct population. Available data suggest important differences in time to presentation, disease pattern and pathways of care between EA and older patients. EA population deserves further detailed investigation, exploring frequency and patterns of EIA and identifying particular issues faced when using adult rheumatology services. Disclosure M. Adas: None. N. Arumalla: None. D. Mclaughlin: None. J. Galloway: Honoraria; from AbbVie, Celgene, Chugai, Galapagos, Gilead, Janssen, Lilly, Pfizer, Roche and UCB. J. Ledingham: Other; is a BSR trustee. F. Mcerlane: None.