Abstract Clinical outcomes in patients with early rheumatoid arthritis (RA) were assessed by baseline symptom duration in the Assessing Very Early Rheumatoid arthritis Treatment trial (ClinicalTrials.gov; NCT01142726). Patients with early, active RA were randomized to subcutaneous (SC) abatacept 125 mg/week plus methotrexate (MTX), SC abatacept alone, or MTX monotherapy for 12 months. All RA treatments were withdrawn after 12 months in patients with Disease Activity Score in 28 joints (C-reactive protein; DAS28-CRP) < 3.2. In this post hoc analysis, the proportion of patients achieving protocol-defined remission (DAS28-CRP < 2.6) or improvement in physical function at 12 and at both 12 and 18 months was assessed according to symptom duration (≤ 3 months, > 3 to ≤ 6 months, or > 6 months) and treatment group. No clinically significant differences were seen in baseline demographics or characteristics across symptom duration groups. Irrespective of baseline symptom duration, a numerically higher proportion of abatacept plus MTX-treated patients achieved DAS-defined remission at month 12 and sustained remission at month 18 compared with MTX monotherapy. A numerically higher proportion of abatacept plus MTX-treated patients with symptom duration ≤ 3 months maintained DAS-defined remission after complete treatment withdrawal from 12 to 18 months compared with longer symptom duration groups. This subgroup also had the fastest onset of clinical response (DAS28-CRP < 2.6) after initiation of treatment. Health Assessment Questionnaire–Disability Index response was similar regardless of baseline symptom duration. Overall, symptom duration of ≤ 3 months was associated with a faster onset of clinical response and higher rates of drug-free remission following treatment with abatacept plus MTX.