We are using the free Microsoft Flow plan, but we require more than the 750 free runs per month. What options do we have?

There are several options to increase the number of Microsoft Flow runs per month:

1. Use Microsoft Flow as a component of Microsoft Office 365 or Microsoft Dynamics 365 Each Office 365/Dynamics 365 user can execute 2000 runs per month as part of the exisiting Office/Dynamics subscription
2. Acquire Microsoft Flow Plans (Plan 1 or Plan 2) per user/month Plan 1 contains 4500, Plan 2 15000 runs per month (assign Plans to users in the Office 365 admin portal)
3. If you require more runs than already available from option 1 or 2, you can separately acquire an additional number of 50000 runs

Important: in contrast to the free Flow Plan, Flow runs included in the Office 365, Dynamics 365, Microsoft Flow Plan 1 and Plan 2 are pooled across all users in the company.

Sources:

Official Microsoft Flow website, retriefed 2018-08-02 (https://flow.microsoft.com/en-us/pricing/) official Microsoft Flow faq website, retriefed 2018-08-02 (https://docs.microsoft.com/en-us/flow/organization-q-and-a)