INTRODUCTION/OBJECTIVES: Ankylosing spondylitis (AS) is a chronic inflammatory immune-mediated condition. We compared AS diagnosis, treatment, and burden in Central Eastern European countries (CEE), where this has been less researched, and the United States (US) from a real-world perspective. METHODS: Point-in-time survey of rheumatologists and their AS patients was conducted in the US (Apr-Oct 2018) and CEE (Aug-Nov 2019) via physician- and patient-completed record forms, including clinical and patient-reported outcomes. Statistical analysis included descriptive statistics, t-tests, Fisher's exact tests, and generalized linear models. RESULTS: In total, 487 patients were recruited from 88 rheumatologists in the US and 922 patients from 126 rheumatologists in CEE. Time from onset of symptoms to final AS diagnosis was longer in CEE than the US (4.2 vs 2.7 years, p < 0.05). At diagnosis, a greater use of conventional synthetic disease-modifying antirheumatic drugs (DMARDs) and injected steroids was reported in CEE vs the US (43.7% vs 27.6%, p < 0.05; 19.3% vs 8.7%, p < 0.05). 22.9% of US patients received a biologic DMARD at diagnosis vs 10% of CEE patients (p < 0.05). At current consultation, biologic DMARD use in CEE was lower vs the US (27.9% vs 71.0%, p < 0.05). CEE vs US patients had greater disease activity (mean Bath Ankylosing Spondylitis Disease Activity Index 4.2 vs 3.1, p < 0.05) and worse quality of life (QoL; mean Ankylosing Spondylitis Quality of Life Questionnaire score 6.2 vs 8.4, p < 0.05). CONCLUSIONS: AS patients in CEE vs the US faced slower diagnosis and worse access to biologics, disease activity, and QoL. Whether early access to biologics can improve symptoms, QoL, and daily activities in AS patients in CEE remains to be seen. Key Points • The study provided evidence on the real-world approach to the diagnosis, treatment, and burden of axSpA (axial spondyloarthritis) in CEE compared with the US. • The study reported patients in CEE experienced longer delays in diagnosis and poorer access to biologics than in the US. • This may have resulted in higher disease activity, greater levels of pain, and poorer outcomes, as reported by patients with axSpA in CEE.