Hello:

Short of a subpoena or a summons, is my tax return viewable by no one BUT the IRS?

excon

Yes and no. If your talking about the paper you turned in then yes. But if your talking about the figures you put down for information then no. Many government agentcies collect data from the IRS to monitor activities of citizens.

Hello again, dad:

How about banks?

excon

No, Banks aren't allowed that information.

Here is the specific rules regarding privacy and your return.

Internal Revenue Code, 26 U.S.C. § 6103

An additional link of interest:

Privacy of Information Reported on Your Tax Return Taxes in the Back

In addition a bank would have no business as far as your filing. Their only concern is to pass along to you and the IRS any documents that pertain to you like interest that you have gained or interest paid by you on a home loan.

This may be so obvious as to not need saying, but of course your tax preparer and your spouse see your return as well. BTW - your tax preparer is not allowed to share any information about your return with anyone other than the IRS without your explicit permission.