Social Security Tax and Withholding Calculator

Enter your expected earnings for 2018 ($):

Social Security Taxes are based on employee wages. There are two components of social security taxes: OASDI and HI. OASDI (Old-Age, Survivors, and Disability Insurance) and HI (Medicare's Hospital Insurance) program. OASDI has been more commonly be known as Federal Insurance Contributions Act (FICA). HI has more commonly known as Medicare. For 2017, the OASDI (FICA) tax rate is set at 6.2% of earnings with a cap at $127,200 (in 2018 this will be increasing to $128,400). The HI (Medicare) is rate is set at 1.45% and has no earnings cap. Employers must pay a matching amount for each tax component. Self employed persons must pay an amount equal to the sum of both the employeee and employer portions.

About these Calculations

  • These tax calculations assume that you have all earnings from a single employer. It is possible to have been overwithheld for OASDI (FICA) taxes in the event that the total of all W2 earning (from multiple employers) for the year (2018) exceed $113,700. HI calculations are unaffected since they are not subject to a wage cap.
  • Self employed persons pay the same as the total of both the employee and employer taxes in total.
  • * Employment related taxes are considered a deductible company expense for employers. Most small and midsize employers are established as a sole proprietorship, partnership, LLC or Sub S corporation. In these entity structures, income passes to the company owners and they are taxed at their personal income bracket rate. For this calculation we have used the maximum tax rate bracket for 2018 of 39.6% (althought that my change if the Bush tax cuts are extended). Get more information on tax brackets for 2018.
  • See this link for history of the contribution and benefits base for FICA (OASDI and Medicare - HI).
  • See this link for history of the tax rates for FICA (OASDI and Medicare - HI).
  • See this link for information about how the average wage base is indexed for wage growth for Social Security taxes.