Autoimmune and paraneoplastic encephalitides are differentials for many neurological syndromes. We aimed to assess which clinical, biochemical and imaging features were associated with positive autoantibodies in suspected cases. Data on patients receiving paraneoplastic/autoimmune encephalitis work-up in St Vincent’s University Hospital over a six-month period were analysed. All patients were tested for one or more of the following antibodies: Anti Hu, Yo, Ri, Ma-1, Ma-2, Tr, Amphiphysin, SOX1, Zic4, CRMP5, NMDAR, VGKC, AMPA-1, AMPA-2, GABA-B, GAD and Glycine. We compared the clinical, radiological and biochemical characteristics of patients with positive versus negative serum antibodies. 215 patients underwent serum autoimmune/paraneoplastic screening between June and December 2018. The most common indications were psychiatric or cognitive disturbance (38.5%) and neuropathies (24.7%). 14 patients (6.5%) had clinically significant positive antibody results. Features most commonly associated with antibody positivity included abnormal basic CSF parameters and visible MRI lesions. 46% of patients received full-body imaging. 34% of these patients required follow-up for non-neurological findings. Our audit revealed low incidence of serum autoantibody detection and the possible important predictive value of CSF analysis. However, despite the investigative burden, appropriate paraneoplastic screening including autoantibody and imaging studies should be performed.