Who is responsible for paying GST Liability (If the Service provider is unregistered) customer is registered

Answer to your question no.1. When a service provider obtains GST registration after crossing 40 lakhs turnover, they typically don't need to revise invoices issued before registration for transactions related to FY 2024-25. Invoices issued before GST registration are considered as being issued by an unregistered person. Post-registration , the service provider should issue invoices as a registered person for transactions happeing after registration. 

For your question no.2: If the service provider is unregistered but the customer is registered: The receipient (registered customer) is liable to pay GST under Reverse Charge Mechanism (RCM) if the service provider is not registered under GST. 

The customer can claim Input Tax Credit (ITC)if eligible as per GST rules. 

Dear Sir,

Thanks for your valuble reply.

If registered customer is not paid GST under RCM till date , Whether there is chances of issue notice to unregistered serivce provider after obtainig GST registration Or registered customer (due to there is difference between GST turnover and income tax turnover FY 2024-2025 of Service provider )

Regards,

Amol