OBJECTIVE: To evaluate factors influencing the development of nonauditory percepts and facial nerve stimulation after cochlear implant (CI) activation. STUDY: Retrospective cohort study. SETTING: Tertiary referral center. PATIENTS: Over the course of 5 years, 433 consecutive patients were evaluated for CI and 518 ears were implanted. Of those, 497 ears had information regarding CI activation. INTERVENTIONS: Lateral wall electrodes (LWE) or perimodiolar/mid-scalar electrodes (PME) were used during implantation. PRIMARY OUTCOME MEASURE: Nonauditory percepts and facial nerve stimulation after activation of CI. RESULTS: Among the 497 devices, which were activated at our institution, 357 (72%) had LWE while 140 (28%) patients had a PME. Of the patients with LWE, 49 (13.7%) patients experienced some form of nonauditory percept. In comparison, 11 (9.2%) patients with a PME had some form of nonauditory percept (p < 0.05). Among the patients who had an LWE, 33 (9.2%) patients had facial nerve stimulation compared with 6 (4.3%) patients with PME (p < 0.05). Additionally, there were 11 (2.2%) patients with incomplete insertion of the electrode who had a significant increase (p < 0.05) in facial nerve stimulation. The mean number of electrodes requiring programming modification to control symptoms was 2.9. CONCLUSIONS: The use of LWE and incomplete insertions significantly increase the rate of nonauditory percepts and FNS after activation of CIs. Otic capsule anomalies are an independent risk factor for both.