Two options come to mind. Recurring invoices let you you set up an invoice once for a customer and then set it to recur on a cycle of your choosing. Broadcast Invoices let you enter one invoice and then send it to multiple customers. The help should have a good description of both features so you can see if one of them will work for you.

Thank you so much for your suggestions! Those both sound like great solutions. 

Hi Victoria, happy to see that the community helped you figure out a solution! 

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