This study investigated the serum and salivary IgG and IgA responses after mRNA vaccination in individuals with and without prior SARS-CoV-2 infection. The study included 427 participants, with 120 having prior SARS-CoV-2 infection and 307 being SARS-CoV-2-naive. Participants were vaccinated with either the BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccines. Serum and saliva samples were collected at multiple time points to measure IgG and IgA levels. Results showed that SARS-CoV-2 spike-specific IgG levels in saliva increased after vaccination in both previously infected and SARS-CoV-2-naive individuals. However, previously infected individuals had significantly higher saliva IgA levels compared to those vaccinated with mRNA-1273. SARS-CoV-2-naive individuals vaccinated with BNT162b2 showed a significant increase in saliva IgA levels only at day 57. Bona fide multimeric secretory IgA levels were significantly higher in previously infected individuals compared to SARS-CoV-2-naive individuals after two antigenic stimulations. The study suggests that mRNA vaccination can induce mucosal immunity in individuals without prior SARS-CoV-2 infection, but at lower levels than in previously infected individuals. Further studies are needed to determine the association between specific saliva IgA levels and prevention of infection or transmission. The findings highlight the importance of mucosal immunity in the context of SARS-CoV-2 vaccination and the potential role of mRNA vaccines in inducing such immunity.This study investigated the serum and salivary IgG and IgA responses after mRNA vaccination in individuals with and without prior SARS-CoV-2 infection. The study included 427 participants, with 120 having prior SARS-CoV-2 infection and 307 being SARS-CoV-2-naive. Participants were vaccinated with either the BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccines. Serum and saliva samples were collected at multiple time points to measure IgG and IgA levels. Results showed that SARS-CoV-2 spike-specific IgG levels in saliva increased after vaccination in both previously infected and SARS-CoV-2-naive individuals. However, previously infected individuals had significantly higher saliva IgA levels compared to those vaccinated with mRNA-1273. SARS-CoV-2-naive individuals vaccinated with BNT162b2 showed a significant increase in saliva IgA levels only at day 57. Bona fide multimeric secretory IgA levels were significantly higher in previously infected individuals compared to SARS-CoV-2-naive individuals after two antigenic stimulations. The study suggests that mRNA vaccination can induce mucosal immunity in individuals without prior SARS-CoV-2 infection, but at lower levels than in previously infected individuals. Further studies are needed to determine the association between specific saliva IgA levels and prevention of infection or transmission. The findings highlight the importance of mucosal immunity in the context of SARS-CoV-2 vaccination and the potential role of mRNA vaccines in inducing such immunity.