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For the person to qualify for the foreign earned income exclusion - he/she should:
-- Work and reside outside the United States for at least 330 days during the year(Physical Presence test), or
-- Meet either the Bona Fide test.
If the person qualifies, he/she may exclude up to $92,900 (2011) in foreign wages. The amount of foreign earned income exclusion fro 2012 is $95,100
To receive that exclusion - the taxpayer should file either form 2555 or 2555EZ. Here are forms you likely need:Form 2555 Instruction 2555
Please be aware that - the exclusion above will not affect self-employment taxes - only income taxes. Only earned income is excludable - income from wages and self-employment. For instance - dividends, investment income, rental income, pensions, etc - are not excludable.
You absolutely may deduct your qualified travel expenses including per diem.
Once you have determined that you are traveling away from your tax home, you can determine what travel expenses are deductible.
You can deduct ordinary and necessary expenses you have when you travel away from home on business. The type of expense you can deduct depends on the facts and your circumstances.
To determine whether you are traveling away from home, you must first determine the location of your tax home. Generally, your tax home is your regular place of business or post of duty, regardless of where you maintain your family home. It includes the entire city or general area in which your business or work is located.
If your assignment or job away from your main place of work is temporary, your tax home does not change. You are considered to be away from home for the whole period you are away from your main place of work. You can deduct your travel expenses if they otherwise qualify for deduction. Generally, a temporary assignment in a single location is one that is realistically expected to last (and does in fact last) for 1 year or less.
However, if your assignment or job is indefinite, the location of the assignment or job becomes your new tax home and you cannot deduct your travel expenses while there. An assignment or job in a single location is considered indefinite if it is realistically expected to last for more than 1 year, whether or not it actually lasts for more than 1 year.
That means - your employer will be required to report your per diem as wages on W2 form if your assignment will be more than a year..