Tax returns are required of all American citizens living outside the U.S. with a certain minimum income. The return filed with IRS includes report of worldwide annual income and a calculation of resultant payment or tax refund.
American citizens who have children under the age of 17 who have a Social Security number are entitled to a refund as long as the parent has a minimal income. The IRS computes all income received as a salaried employee or as an independent worker; it is required to present salary slips, Form 106 and a tax assessment.
There are some types of income that are not included in the computation of a refund, but are considered as income for tax purposes – passive income such as rental fees from a property, National Insurance (Bituach Leumi) payments, even parental support.
Also required is Form 1099 of US Income Declaration listing stocks, investments, income from sales or rentals etc.