Depending on what type of license you have, not renewing maintenance or subscriptions has different outcomes. If you are unsure of how your product is licensed, please reach out to your Customer Success Manager.
When your subscription expires, your access to Tableau will be suspended. For Tableau Online customers, access to your Tableau Online site will also be suspended. Further, Tableau cannot guarantee you will have access to any content published to Tableau Online, including any data input into the product.
Perpetual Licenses & Maintenance
If your Tableau licenses are perpetual, you may continue to use the product in perpetuity after your maintenance expires. You can continue to use the last available version while your maintenance was active indefinitely; but access to product upgrades and technical support will not be available without a current maintenance contract. If you opt not to renew, please keep a copy of the Software as Tableau will not guarantee supporting the download in perpetuity.
For more details see the Tableau Subscription & Maintenance Policy.