The U.S. Treasury has published model IGAs that follow two approaches. In the case of Model 1, financial institutions in the partner country report information on U.S. accounts to the tax administration of the partner country. This tax authorities then make the information available to the United States. Model 1 is available in a mutual version (Model 1A) in which the United States also shares information about partner country taxpayers with the partner country, and a non-reciprocal version (Model 1B). In the case of Model 2, partner country financial institutions report directly to the Domestic Revenue Department of the Netherlands and the partner country agrees to reduce all legal barriers to this report.  Model 2 is available in two versions: 2A without Tax Information Exchange Agreement (TIEA) or Double Tax Convention (DTC) and 2B for countries that already have an existing TIEA or DTC. Agreements usually have to be approved by Parliament in the countries with which they are concluded, but the United States does not want to be ratified as a treaty.
Previously, there were few reliable estimates of the additional burden of the internal income service, although it seems certain that the bulk of the costs are likely to be borne by the financial institutions concerned and (to a lesser extent) the foreign tax authorities, which have signed intergovernmental agreements.   The FATCA bill authorized an additional 800 IRS members (estimated cost between $40 million and $160 million per year). According to a TIGTA report, the cost of developing the FATCA XML data site is $16.6 million ($2.2 million above budgeted). “Irs has also filed a budget request of $37.1 million to fund the implementation of FATCA for 2013, including the costs of personnel controllers and agents dedicated to the implementation of FATCA, as well as IT development costs. This budget request does not identify the resources needed for implementation beyond the 2013 financial year” The I.R.S. has not been able to determine all potential costs beyond the cost of IT resources.  In April 2014, the U.S. Treasury and the IRS announced that all jurisdictions that enter into “essential agreements” and agree to have their compliance status published by July 1, 2014 would be treated as if they had implemented an IGA until the end of 2014, to ensure that no sanctions would be imposed during that period, while more jurisdites will be able to: Finalize formal IEAs.   With Canada`s agreement in February 2014, all G7 countries signed intergovernmental agreements.
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