European Union

A 2010 study published in L'Anglophone,^[7] a Brussels newspaper, compared the tax burdens of "Average Joes" in each of the 27 EU member states and projected the Tax Freedom Day for workers earning a typical wage. Income taxes, social security contributions (by the employee and the employer) and projected VAT contributions were included in the calculations.

Regarding the discrepancy between their calculation of August 3 as the typical Belgian worker's Tax Freedom Day and that of PriceWaterhouseCoopers (PWC), L'Anglophone's authors wrote:^[8]

[PWC's] figures count revenue from all taxes (including those on corporate profits, petrol, cigarettes, &c.) and thus present a more complete picture of the country’s total tax burden," adding that it is "an average applied to all Belgians – not all Belgian workers; in 2008, less than half of Belgium’s population (4.99 million working out of 10.67 million citizens) was legally working. Consequently, a huge share of Belgium’s tax burden is borne by the working population.

Mathematical

For Canada, the Fraser Institute also includes a "Personal Tax Freedom Day Calculator" that estimates a customized Tax Freedom Day based on additional variables such as age of household head, sex of household head, marital status and number of children. However, the Fraser Institute's figures have been disputed. For example, a 2005 study by Osgoode Hall Law Professor Neil Brooks^[10] argued that the Fraser Institute's Tax Freedom Day analysis includes flawed accounting, including the exclusion of several important forms of income and overstating tax figures, moving the date nearly two months later.^[11]

In America, while Tax Freedom Day presents an "average American" tax burden, it is not a tax burden typical for an American. That is, the tax burdens of most Americans are substantially overstated by Tax Freedom Day. The larger tax bills associated with higher incomes increases the average tax burden above that of most Americans.

The Tax Foundation defends its methodology by pointing out that Tax Freedom Day is the U.S. economy's overall average tax burden—not the tax burden of the "average" American, which is how it is often misinterpreted by members of the media.^[12] Tax Foundation materials do not use the phrase "tax burden of the average American", although members of the media often make this mistake.^[13]

Another criticism is that the calculation includes capital gains taxes but not capital gains income, thus overstating the tax burden. For example, in the late 1990s the US Tax Freedom Day moved later, reaching its latest date ever in 2000, but this was largely due to capital gains taxes on the bull market of that era rather than an increase in tax rates. In other words, variations in capital gains income and their associated taxes cause changes in the amount of taxes, but not in the income used in the calculation of Tax Freedom Day.

The Tax Foundation argues that the Tax Freedom Day calculation does not include capital gains as income because it uses income and tax data directly from the Bureau of Economic Analysis (BEA). BEA has never counted capital gains as income since they don't represent current production available to pay taxes, and so the Tax Foundation excludes them as well. Additionally, the Tax Foundation argues that the exclusion of capital gains income is irrelevant in most years since including capital gains would only shift Tax Freedom Day by 1 percent in either direction in most years.^[14] A 1 percent change would represent 3.65 days. From 1968 to 2019 the date has never left the 21-day range of April 13 to May 3.