Sarib Madni

Hello, my client has an eBay seller account in the UK, he has an LTD registered and attached to his eBay account. He is a resident of the USA. Please help me with how we can apply for the National Insurance Number as eBay payouts are on hold for our account. Also, help me if there's an option to get an NI number if the foreign seller doesn't have an LTD registered. Thank you very much for your help