Swiss bank account? Better report it now.

The IRS has made an offer to Americans with unreported offshore accounts: Turn yourself in, and you won't face possible time in jail or fines as high as usual. The partial amnesty program started in February, and the offer extends to Aug. 31, 2011.

Normally, if somebody volunteers to come forward with an undisclosed account, the penalty will be less severe than if they're nabbed. This program makes that penalty even lighter, though IRS Commissioner Doug Shulman says it's "a steep price."

The IRS made a similar "last chance" offer two years ago, but they say this time really is the final chance to come clean for such a mild penalty. The 2009 program had lower fines than this year's: 15,000 Americans reported previously undisclosed foreign accounts.