To characterize speech perception performance in elderly cochlear implant users compared with younger adult users. Case-control retrospective analysis from January 1, 1999, to January 28, 2008. Tertiary care, academic practice cochlear implant program. Medical records for 78 patients with age at implantation of 65 years or older were analyzed for ear-specific preimplantation speech perception performance, length of deafness, age at implantation, and 1-year postimplantation speech perception performance. A subset of 28 elderly patients with complete data was matched to 28 younger adult patients (age at implantation, 18-64 years) for preimplantation performance using the Hearing in Noise Test-Quiet scores (mean, 22% and 23%, respectively). One-year postimplantation performance on word and sentence testing. Within the elderly cohort, the Consonant-Nucleus-Consonant and Hearing in Noise Test-Quiet scores were not affected by age. The Hearing in Noise Test-Noise scores trended downward with increasing age but did not reach statistical significance (P = .052). Of the matched older and younger patients, 55 of 56 showed improvement in their 1-year postimplantation compared with preimplantation Hearing in Noise Test-Quiet scores, with better preimplantation performance predictive of better postimplantation performance, independent of age at implantation (P = .02). Group comparisons, however, revealed poorer postimplantation scores overall for the elderly patients compared with the younger ones for the Hearing in Noise Test-Quiet (70% vs 83%; P = .02) and the Consonant-Nucleus-Consonant test (38% vs 53%; P = .02). Elderly patients benefit significantly from cochlear implantation. Compared with a younger cohort matched for preimplantation performance, however, their postimplantation scores are significantly lower on some measures. These results may provide guidelines for candidacy and counseling regarding elderly patients with cochlear implants.