In the USA also, the return may be filed electronically or the physical copy mailed to the IRS. As a uniform PRACTICE, 6KM would prepare the return and the PDF copy of the US tax return would be mailed to the taxpayer along with filing instructions.
The taxpayer would then take a printout of the tax return, verify and sign the same and mail it to the IRS.
The refund if any would be usually transmitted to the SPECIFIED bank account directly or to mailing address depending on detail provided.
The taxpayer has to track the status of the refund in case the same is not received WITHIN a reasonable period of TIME.