Hello @Khushboo Kumari ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you would like to know how many connections can be created for one ExpressRoute circuit.
You can create a connection to link a virtual network to an Azure ExpressRoute circuit. The virtual networks that you connect to your Azure ExpressRoute circuit can either be in the same subscription or part of another subscription.
You can have up to 10 virtual networks connections on a standard ExpressRoute circuit, and up to 100 on a premium ExpressRoute circuit depending upon the circuit size.
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