Thank you for reaching out.
I understand you wish to know if there will any additional charge which you need to pay to the service provider to enable connectivity to ExpressRoute.
Actually, there is a note here in the Express Route Pricing document which states
Customers may incur additional charges by their service providers to enable connectivity to ExpressRoute.
I think you can reach out to your service provider and check if there is any charge for enabling connectivity to ExpressRoute.
If it helps you can also get one-on-one guidance on Azure pricing. Azure Pricing Calculator is also a good resource you can explore.
Hope this helps! Please let me know if you have any additional questions. Thank you!
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