what does "a physical presence in the United States" mean?
A physical presence (or nexus) for your business typically means that you have a store or warehouse in that location. However, the definition of a physical presence or nexus can differ between states, so I recommend checking in with a local tax professional if you're looking into this for tax purposes.
As far as Shopify Payments payouts go, the physical presence is in reference to the bank having an actual physical location. For example, if you want to receive payouts in USD, your bank account must be with a physical bank in the United States (noted in the bank account requirements for Shopify Payments). This means that the bank can't be a virtual institution that exists only online.
Company isn't registered or trading from the US however we do have a bank
based locally in the US.
I just want to make sure I'm caught up here in case anything has changed. You mentioned previously that your business is operating from the UK and that you were selling to the US, EU, and UK. Is that correct?
I know that you were considering opening multiple stores in order to be paid out in USD, EUR, and GBP respectively. However, signing up for a new Shopify store with the UK address for your business means Shopify Payments would be available to you in GBP only. For example, you would need to sign up with a US address in order to use Shopify Payments in the United States and get paid in USD.
You had also mentioned that the US bank account was with a virtual bank, which isn't compatible with Shopify Payments at this time. You can still sell in multiple currencies so that customers can checkout in USD, EUR, or GBP, but as we previously discussed, those payments would then be converted to GBP for your payouts.
I can submit feedback to our developers on your behalf in case Shopify Payments is able to offer multiple payout currencies on one account going forward. Please let me know if there are any details you would like to provide about why separate payout currencies rather than conversion to GBP is ideal for your business. In the meantime, a third-party payment provider might be the best solution.