The list that nun linked too is interesting. For instance I am not listed there at all (and indeed several other US tax advisers I know are also missing).
For instance. unfortunately whether or not a green card is valid for immigration purposes has no effect on US tax. For US tax purposes a US green card holder is still subject to worldwide US taxation until both the green card has been officially surrendered the to a US consular officer AND a SPECIAL tax return for the year the green card was given up has been filed. (In some circumstances US tax returns also need to be filed for the 10 years after the green card is given up even after these actions.)
I think there is a "long term residence" criterion that's applied to Green Card holders, something like having been a US resident for 8 out of the last 15 years. Here is something I found about just how hard it is to give up that Green Card (for tax purposes anyway). These rules my seem
terrible, but actually I don't think most people will have too much US tax to pay because of the foreign earned income exclusions and the
existance of tax treaties that eliminate most double taxation. The important thing is to have a plan and comply with the law, it might be a pain to have to file these taxes and as a Green card holder you might think "heck what right does Uncle Sam have to follow me home", but a bit of time spent filing forms will avoid the potential of fines and will probably cost you very little if anything in extra tax
Expatriation rules
US citizens who renounce their citizenship and long-term residents (defined as individuals who have had a green card for eight out of the past 15 years) who surrender their green card with a principle purpose of avoiding US taxes are subject to an alternative tax regime for the 10 years following the expatriation. Under this regime, the individual is subject to US tax on a broad scope of US source income generally at tax rates applicable to US citizens. Whether tax avoidance is a principle purpose for expatriation is a subjective determination, although certain individuals are treated as having such a principle purpose based on the individual’s US federal tax liability for the five preceding tax years or the individual’s net worth on the date of expatriation.
A tax avoidance motive is presumed if the following tax liability or net worth tests were met:
* the individual had an average annual net income tax liability in excess of US$124,000 for the five-year period preceding the date of expatriation; or
* the individual had a net worth of US$622,000 or more on the date of expatriation.
The act introduces significant changes to the expatriation provisions effective to persons who expatriate after June 3, 2004. Changes include:
* Objective standards replace the subjective standards to determine whether the expatriated individuals are subject to the alternative tax regime.
* An expatriated individual will continue to be treated as a US resident until the individual gives notice of an expatriating act or termination of residency to the Secretary of State or the Secretary of Homeland Security, and provides a statement under Section 6039 (G).
* The net worth test (as described) will increase to US$2 million from US$622,000, but it will not be adjusted for inflation. The average tax liability figure of US$124,000 referred to above will be indexed for inflation.
* An individual subject to the alternative tax regime will be required to file a tax re- turn for the 10 years following expatriation regardless of whether any US federal income tax is due. The penalty for noncompliance is US$10,000.
* An expatriated individual subject to the alternative tax regime who is physically present in the US for more than 30 days in any given calendar year during the 10-year period following expatriation will be subject to full US federal taxation in that year.
* Even if the individual is below the threshold of tax liability or net worth tests, he or she must still certify, under penalties of perjury, that they have complied with all of the US federal tax obligations for the preceding five years. In addition, evidence of compliance may be required.
* Gift taxes will apply in some situations.
The ongoing filing obligations can put a significant administrative burden on individuals relinquishing their US citizenship or US residency in the case of expatriates.
From a US federal tax perspective, a nonresident alien individual entering the US should consider obtaining a visa other than a permanent residence visa (green card). If an individual obtains a green card, such individual should avoid becoming a long-term resident by not being taxed as a resident for more than seven years.