I'm Ava from Shopify Support, I'd like to help clarify this for you.
You can use the same bank account for multiple Shopify stores if you like! You are free to start more than one store, many merchants have several stores that sell different kinds of products. For example, you may want to open one store that specializes in furniture & homewares, and another that specializes in technology and appliances. You can use one bank account for both of these stores when setting up your payment gateway to accept payments from customers.
However, if you are asking if you can use one Shopify subscription to link multiple Shopify stores to, then I'm afraid this is not possible. There can only be one admin section per Shopify subscription. So if you wanted more than one store, you would need to open multiple accounts.
Let me know what you think!
Ava Social Care | help.shopify.com
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