Decoding Your W-2

By: Prachi Patke, CFA

Ah, the W-2 form—that annual document you get from your employer, which you hastily sent off to your accountant or plugged into TurboTax without a second glance. But have you ever paused and wondered, 'What do all these numbers mean?' and 'How did they even come up with these figures?' While tax calculations can vary wildly depending on everyone's specific income and situation, it's still a mystery shrouded in payroll paperwork for most of us. Let’s unravel this mystery and dive into each of the various boxes on the form to decode your W-2.

Box 1: Total Taxable Gross income

If your gross income (base pay) is $1,000, Box 1 would show $1,000, assuming all of it is taxable. 

Box 2: Federal income tax withheld

Shows the total amount of federal income tax withheld from your paycheck for the year. Assuming a federal tax rate of 10%, Box 2 would show $100 (10% of $1000). 

Box 3: Social Security wages

The part of your income that is subject to Social Security tax, which may differ from Box 1 due to the Social Security wage base limit. What is this base limit, you ask? 

Social Security wages may differ from your total taxable income reported in Box 1 for several reasons. A base limit for social security tax is determined every year, adjusted annually for inflation. For 2023, this limit was $160,200. If your total earnings (Box 1) exceed this limit, only the amount up to that limit will appear in this box. In comparison, Box 1 shows all taxable income. Certain pre-tax deductions, such as contributions to a 401(k) plan reduce your taxable income but not your Social Security wages. This means even if your taxable income (Box 1) decreases due to such deductions, your Social Security wages (Box 3) might remain higher, reflecting the total earnings subject to Social Security tax. 

To decode these tax-related terminology like pre-tax, post-tax etc., refer to this article on Unraveling Tax Jargon. 

Since in our example, our total income in our example is (unapologetically) below the 2023 Social Security base limit of $160,200, our Box 3 would show $1,000, same as Box 1. 

Quick Tip: If you’re not a U.S. resident for tax purposes — whether you’re an international visitor or working on specific visas — you might be exempt from Social Security and Medicare taxes. Double-check this, as it could save you a bunch of paperwork and a trip to the IRS later! Check out the IRS website for more information to decide if your visa / tax residence status allows you to be exempt from these taxes. 

Box 4: Social Security tax withheld

The amount of Social Security tax withheld from your earnings. So, with a Social Security tax rate of 6.2% to our $1,000 income (Box 3), this box would show $62 (6.2% of $1,000). 

Box 5: Medicare wages and tips

Box 5 reports the total wages and tips subject to Medicare tax. Unlike Social Security wages, there is no wage base limit for Medicare taxes; all earned income is subject to these taxes. Therefore, Box 5 typically matches the amount in Box 1 unless there are specific types of pre-tax deductions that do not affect Medicare wages, such as 401(k) contributions. In most cases, if Box 1 and Box 5 differ, it’s due to specific fringe benefits or other uncommon adjustments. 

Box 6: Medicare tax withheld

The amount of Medicare tax withheld from your earnings. With a Medicare tax rate of 1.45%, Box 6 would show $14.50 (1.45% of $1000).

Boxes 7-15

Boxes 7 through 15 on the W-2 form deal with specific situations that may be relevant only to certain types of employees and their elections. Boxes 10 through 14 cover various other deductions and benefits such as dependent care benefits and retirement plan contributions, which vary widely among employees. Let’s quickly define these boxes and move on. 

Box 7: Social Security Tips

Just like the tip you leave at a restaurant, Box 7 shows any tips you've reported to your employer that also need Social Security tax paid on them.

Box 8: Allocated Tips

Think of allocated tips like the surprise extra fries at the bottom of your takeout bag – a pleasant surprise but you still have to report them if they’re substantial. These are tips the IRS thinks you received but that weren’t reported, added onto your wages.

Box 9: Advance Earned Income Credit (EIC) payment

Imagine getting an advance on your paycheck; that’s what Box 9 is, but for the Earned Income Credit — extra money given to you by your employer, part of a tax credit advance.

Box 10: Dependent Care Benefits

Box 10 is like a daycare voucher. It shows any money spent from your salary (up to $5,000) on things like childcare, which lets you work and earn that $1,000.

Box 11: Nonqualified Plans

Some corporates allow executives to defer larger parts of their compensation to defer tax – these are called NQDC Plans.  This box is where any amounts distributed to you from nonqualified deferred compensation plans (NQDC Plans) may be reported. 

Box 12: Codes

Box 12 lists various codes that explain different deductions or contributions, from retirement plans to health insurance, all affecting your paycheck. You can find a complete list of the codes in the box instructions on the W-2 Form.

Box 13: Retirement Plan Checkbox

If checked, it’s like saying, "Yes, I’m saving for the future!" This box shows whether you’re contributing to a retirement plan like a 401(k). 

Box 14: Other

Think of Box 14 as the junk drawer — it holds a mix of different items that don’t fit elsewhere, like union dues, health insurance premiums, etc.

Box 15: State and Employer's State ID Number

Box 15 is straightforward; it lists your employer’s state and state tax ID number — basic info needed just like your address when filing state taxes.

Now, onward to Boxes 16-19.

Box 16: State wages, tips, etc.

This is the part of your income that is subject to state taxes. For those of you who may have lived in more than one state over the course of the year, you will see a new line entry for the income you earned while living in that state and the corresponding state taxes incurred on that income. 

For someone living in Manhattan, NY, Box 16 would show $1,000, assuming all income is taxable at the state level.

Box 17: State income tax

This is the state tax calculated on the income earned in that state (Box 16). So, with our example, assuming a New York state tax rate of 6%, Box 17 would show $60 (6% of $1000).

Box 18-19: Local wages, tips, etc. and Local income tax

These boxes show the amount of earnings subject to local (city) taxes and the actual tax calculated on them. For example, living in Manhattan costs you an additional city tax based on your income bracket. (“Who’s laughing now!”- overheard from the other side of the river.)

Assuming you earned all of your income as a resident of Manhattan, and assuming a city tax rate of 4%, Box 18 would show $1,000 and Box 19 would show $40 (4% of $1,000). 

That’s all, folks! Hope this crash course reading can ease at least some of your tax-related frustrations. In the very least, you’re all set to tackle your taxes with confidence and maybe even impress your accountant a little bit!

This article is for educational purposes only and is not intended to provide or replace professional tax advice. The information contained herein is meant to explain certain financial and tax-related terms and concepts. Individuals should consult with financial advisors, tax professionals, or other personal consultants to obtain advice tailored to their specific situation and to make informed decisions about their financial planning and tax strategies.