APRIL 15 is dreaded as the deadline for filing income tax returns, but in fact every day is tax day for most working people. That’s because more than half of all Americans pay more in payroll tax than in income tax. That includes nearly everyone in the bottom half of the income distribution.

We don’t file annual payroll tax returns because payroll taxes have one rate and they aren’t adjusted for individual differences that affect taxpaying ability. Your bill remains the same regardless of how many children you support, your medical or education expenses, or your charitable contributions. No standard deduction or personal exemption either: payroll taxes apply to the first dollar.

Since they were introduced in 1937, payroll taxes have risen from two cents to more than 15 cents for every wage dollar earned. Although the tax is technically split between employers and employees, economists agree that workers suffer the whole cost of the tax. Without it, workers could expect to have higher wages, not just lower taxes.

The social insurance rhetoric surrounding the payroll tax might lead you to think that you are paying for your future retirement benefits. That’s not how it works, though: current taxes pay for current benefits. The Social Security “trust fund”? That’s an accounting mechanism, not an actual pot of money.