Vial was expired on 13-Aug-2022 and stored in refrigerator on 12-Sep-2022 and administered to the patient on 13-Sep-2022; No adverse event; Second booster dose of expired Moderna Covid-19 vaccine (Monovalent) administered to patient; Patient received 0.5 ml as second booster dose; This spontaneous case was reported by an other health care professional and describes the occurrence of EXPIRED PRODUCT ADMINISTERED (Second booster dose of expired Moderna Covid-19 vaccine (Monovalent) administered to patient), PRODUCT STORAGE ERROR (Vial was expired on 13-Aug-2022 and stored in refrigerator on 12-Sep-2022 and administered to the patient on 13-Sep-2022), ACCIDENTAL OVERDOSE (Patient received 0.5 ml as second booster dose) and NO ADVERSE EVENT (No adverse event) in a 69-year-old patient of an unknown gender who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 057M21A) for COVID-19 vaccination.     No Medical History information was reported.   On 13-Sep-2022 at 10:08 AM, the patient received fourth dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to .5 milliliter. On an unknown date, the patient received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form and first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 13-Sep-2022 at 10:08 AM, the patient experienced EXPIRED PRODUCT ADMINISTERED (Second booster dose of expired Moderna Covid-19 vaccine (Monovalent) administered to patient) and ACCIDENTAL OVERDOSE (Patient received 0.5 ml as second booster dose). On an unknown date, the patient experienced PRODUCT STORAGE ERROR (Vial was expired on 13-Aug-2022 and stored in refrigerator on 12-Sep-2022 and administered to the patient on 13-Sep-2022) and NO ADVERSE EVENT (No adverse event). At the time of the report, EXPIRED PRODUCT ADMINISTERED (Second booster dose of expired Moderna Covid-19 vaccine (Monovalent) administered to patient), PRODUCT STORAGE ERROR (Vial was expired on 13-Aug-2022 and stored in refrigerator on 12-Sep-2022 and administered to the patient on 13-Sep-2022), ACCIDENTAL OVERDOSE (Patient received 0.5 ml as second booster dose) and NO ADVERSE EVENT (No adverse event) outcome was unknown.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered NO ADVERSE EVENT (No adverse event) to be not related. No further causality assessments were provided for EXPIRED PRODUCT ADMINISTERED (Second booster dose of expired Moderna Covid-19 vaccine (Monovalent) administered to patient), PRODUCT STORAGE ERROR (Vial was expired on 13-Aug-2022 and stored in refrigerator on 12-Sep-2022 and administered to the patient on 13-Sep-2022) and ACCIDENTAL OVERDOSE (Patient received 0.5 ml as second booster dose).    No concomitant medications were reported.  Reported that patient received 2 COVID doses and 2 booster dose. The vaccine was delivered and placed into the freezer on 18-Apr-2022.  Vaccines were only offered on Tuesdays from Mar-2022 forward. For each Tuesday vaccine date, only one vial was removed from the freezer to place in the refrigerator the day before it was used (each Monday, one vial was removed from the freezer and placed into the refrigerator). Therefore, for administration on 13-Sep-2022, vial was removed from the freezer and placed into the refrigerator on 12-Sep-2022. The vial did not undergo any temperature excursion.  No treatment medications were reported.