You can wire money to any account in the world. It’s a way to pay bills. I wired 20k out of my brokerage yesterday to pay for a piece of art. IB must let you wire money to pay for big ticket items.
Nope. I think Schwab allows that, but my impression is that most do not. It is not IB's fault. The problem is stricter regulation and bigger fines. IB just settled a suit before this change. It is my impression that IB had done nothing wrong other than allocating pro rata less to KYI and AML compared to the growth of their business. It is problematic. Let's say IB earns USD 100.000 annually on a client. The client has a regular bank account at a local bank. The local bank does not earn anything significant on the relationship. The client needs to open a corporation account at IB instead of a personal account and needs to transfer let's say USD 2 million from the personal IB account to the corporation account at IB. If IB refuses, the client needs to transfer USD 2 million to the regular account at a local bank. The local bank needs to pay the costs associated with making sure KYC and AML regulation is adhered to. Then the USD 2 million is transferred back to IB. Many regular banks will refuse to do that because it will just cost them money and put them at risk. The loser is the client who has done nothing wrong but may realize it is not possible to fund the corporate account. A legitimate reason to open a corporate account can for instance be changes in the tax code that makes the marginal tax rate lower when investing through a corporation etc.
E*TRADE allows it. Vanguard allows it. Probably 2x a year i transfer money to other entities, some on the order of your hypothetical example. It’s a serious lacking in a service that would benefit wealthy people who have private investments.