Not 100% sure, but in the case of Super extraction and use in the USA I think you would be fairly safe. Super has tax paid on it on input, so under the treaty you would probably be able to direct transfer the lot with just the Aussie fees involved. But that of course depends how your super works, whether its lump sum or not. I have friends now Australian citizens and residents who received overseas payments for similar things (retirement type funds) and if it was taxed there at some point it's just paid into an account, although most are below the threshold for any real taxation. Best option on large sums is get professional advice, especially if it involves shares and investments outside cash, getting tax wrong is a big no no in the USA. The IRS has legendary powers.