A method for managing storage space for electronic messages. A computer receiving a selected time period in which a user of a messaging program will not be able to access electronic messages through the messaging program. The computer estimating, by one or more computer processors, an amount of storage space required to store electronic messages received during the selected time period. The computer determining, by one or more computer processors, that an unused portion of storage space allocated to the user is less than the estimated storage space required. The computer notifying the user that the unused portion of storage space allocated to the user is less than the estimated storage space required.