Patients with kidney failure treated with maintenance dialysis have an increased risk of severe disease due to SARS-CoV-2 infection, the virus that causes COVID-19. Previous studies have shown that COVID-19 vaccination is effective against severe COVID-19 illness in the general population. However, less is known about populations at greater risk for severe disease. This investigation examined the real-world effectiveness of bivalent mRNA COVID-19 vaccination against clinical outcomes among patients treated with maintenance dialysis.