# Storage of email campaign reports Email campaign reports are retained for a period according to the package purchased. **The minimum retention time is 3 months.** Depending on the selected plan, this period may be extended. **Information on undelivered messages** (addresses to which messages could not be delivered) is retained for **10 days after sending.** ### Email message billing Billing of email messages is stored for 40 days after shipment. Such billing includes information such as: * recipient's email address, * the date the message was sent, * the status of the message. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.messageflow.com/email/e-mail-campaigns/analytics-audiences-and-reports/storage-of-email-campaign-reports.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.