Abstract Aims The study aimed to investigate the prevalence, phenotypic characteristics, and predictors of atrial fibrillation (AF) in patients presenting with cardiac amyloidosis (CA) of light‐chain (AL) or transthyretin (ATTR) type. Methods and results Clinical, biochemical, and echocardiographic data of patients presenting with CA between 2005 and 2020 were retrospectively collected. CA staging was based on established biomarker systems. Binomial logistic regression was run to analyse the effects of clinical variables on the likelihood of AF. The study included 133 patients [53% AL, 41% wild‐type (wt) ATTR‐CA, & 6% hereditary ATTR‐CA]. Mean age was 71 years, and 80% were male patients. AF was diagnosed in 64 (48%) patients (28% in AL‐CA, 80% in wtATTR, 13% in hATTR, P