The day you renounce your US citizenship, you are no longer a US person (unless the State Department has a valid reason to deny your renunciation). It may take

The day you renounce your US citizenship, you are no longer a US person (unless the State Department has a valid reason to deny your renunciation). It may take several months, or more than a year, for the State Department to issue you your Certificate of Loss of Nationality (CLN). However, the effective date of your loss of citizenship is the day you signed the papers and swore your oath of renunciation at the Embassy or Consulate. You are only required to file taxes with the IRS for the year you renounced, and only for whatever you earned up to the date of your renunciation. Before the HEART Act of 2008, you may have been required to continue filing, and paying US taxes. However, that has now been replaced with a one-time exit tax on unrealized gains, for "covered expatriates" (http://en.wikipedia.org/wiki/Expatriation_tax http://en.wikipedia.org/wiki/Expatriation_tax).