The uptime guarantee for QuickBooks Enterprise Hosting can vary depending on the hosting provider you choose. Different hosting providers may offer different service level agreements (SLAs) with varying uptime guarantees. It is recommended to check with the hosting provider directly or review their terms of service to determine the specific uptime guarantee they offer.

Typically, reputable hosting providers strive to provide high uptime percentages, often exceeding 99%. This means that the service is expected to be available and accessible for the majority of the time, with minimal downtime for maintenance or unexpected issues. Hosting providers usually have measures in place to ensure redundancy, backup systems, and disaster recovery procedures to minimize downtime and maximize service availability.

When considering a QuickBooks Enterprise Hosting provider, it's essential to inquire about their uptime guarantee, any compensation or remedies they provide in case of failure to meet the guarantee, and their track record in delivering reliable and uninterrupted hosting services.