OASDI Tax: What It Is and Who Pays It

The OASDI tax is one of two FICA payroll taxes that go toward Social Security and Medicare.

Many, or all, of the products featured on this page are from our advertising partners who compensate us when you take certain actions on our website or click to take an action on their website. However, this does not influence our evaluations. Our opinions are our own. Here is a list of our partners and here's how we make money.

Updated Feb 7, 2025 · 2 min read

Written by

Lead Writer

+ more

Reviewed by

Certified Financial Planner®

+ more

Edited by

Editor & Content Strategist

+ more

Are you curious about those taxes on your paycheck and wondering what they’re for? One of them is the OASDI tax, which, for some workers, might be a significant chunk of their pay.

What is OASDI tax?

Also known as Social Security, the OASDI (Old-Age, Survivors, and Disability Insurance) tax is one of two taxes that make up the Federal Insurance and Contributions Act (FICA). The other is a Medicare tax.

OASDI tax provides financial support to those who have lost income due to retirement, disability or death.

The OASDI tax rate is 6.2% for employees and 12.4% for self-employed people, up to a certain income limit. Collectively, OASDI and Medicare taxes amount to 15.3%.

» Learn more: How FICA taxes work on your paycheck

How does OASDI tax work?

If you’re an employee, the 12.4% OASDI tax is split evenly between you and your employer. This means that 6.2% is automatically deducted from your paycheck, and your employer pays the other 6.2%. It’s considered an additional expense for your employer and won’t be further deducted from your pay.

» MORE: How other types of withholding taxes are calculated

5.0

NerdWallet rating

Start Now

Federal: $79 to $139. Free version available for Simple Form 1040 returns only.
State: $0 to $69 per state.
Expert help or full service filing is available with an upgrade to Live packages for a fee.

Start Now

Disclosures: TurboTax Free Edition is for Simple Form 1040 returns only (no schedules except for Earned Income Tax Credit, Child Tax Credit and Student Loan Interest). Roughly 37% of taxpayers qualify.

OASDI tax for self-employed people

If you’re self-employed, you’ll pay both the employee and employer portions of the OASDI tax. That means you’re responsible for the full 12.4% and will have to calculate it yourself (or with the help of a tax pro). OASDI taxes can be paid as often as monthly but are due quarterly. Paying taxes late could result in a bigger tax bill, along with penalties and interest.

While it’s a little extra work, there’s some good news for entrepreneurs: You’re able to deduct half the OASDI tax paid on your annual tax return. Other options, such as forming an S-corporation, could also help lower your OASDI tax.

» MORE: Other self-employment tax deductions

OASDI limit 2025

The OASDI limit for 2025 is $176,100 — a $7,500 increase from 2024. This is also called the taxable maximum, meaning that any income above this limit is not subject to OASDI taxes.

As a result, employees will contribute a maximum of $10,918.20 to Social Security, while self-employed people will contribute a maximum of $21,836.40.

Is OASDI tax mandatory?

The OASDI tax is mandatory for most people, but there are exceptions. Any income above the taxable maximum is not subject to the Social Security tax. Those who are self-employed and make less than $400 per year are also exempt.

Local and state government employees are also exempt if they’re only covered by their state or local pension plan. Certain nonimmigrants and nonresidents, depending on the type of visa held, are also granted exemptions. This includes foreign students, researchers and academics at universities, as well as foreign government employees working in the U.S.

Certain religious groups are exempt from Social Security and Medicare taxes, but individuals need to file Form 4029 and receive approval from the IRS. Doing this also waives their right to benefits in the future.

» Dive deeper: What does it mean to be tax-exempt?

5.0

NerdWallet rating

Start Now

Federal: $79 to $139. Free version available for Simple Form 1040 returns only.
State: $0 to $69 per state.
Expert help or full service filing is available with an upgrade to Live packages for a fee.

Start Now

Frequently Asked Questions

Is OASDI tax the same thing as Social Security tax?

Yes. OASDI is commonly called Social Security, so the Social Security tax also refers to the OASDI tax.

Can I get my Social Security tax back if I’ve overpaid it?

Maybe. This could happen under certain circumstances, such as if you work two jobs and the combined income is above the annual taxable maximum. In this scenario, both of your employers may have withheld too much of your pay for Social Security tax.

To correct this, you may be able to claim the excess OASDI tax on your income tax return to receive a refund.

Article sources

NerdWallet writers are subject matter authorities who use primary, trustworthy sources to inform their work, including peer-reviewed studies, government websites, academic research and interviews with industry experts. All content is fact-checked for accuracy, timeliness and relevance. You can learn more about NerdWallet's high standards for journalism by reading our editorial guidelines.