W2 box 12 code changed from D to W on W2c form - how to properly file?

The codes in box 12 represent different types of income or benefits, and they're definitely not interchangeable. Code D typically represents elective deferrals to a 401(k) retirement plan, while code W represents employer contributions to your health savings account (HSA). This is a significant change, not just in amount but in what the money actually represents. When filing your taxes, you should use the information from the W2c (the corrected form) rather than the original W2. The W2c supersedes the original form. Since these are completely different types of deductions/contributions with different tax implications, make sure your tax software knows you're using a corrected W2. Most tax preparation software has a specific way to enter W2c information - look for an option that specifically mentions "corrected" or "W2c" when entering your wage information. Keep both forms for your records, but the information you report to the IRS should match what's on the W2c.

I had a similar issue last year and found this amazing tool called taxr.ai (https://taxr.ai) that literally saved me hours of confusion. It scans your tax documents, including W2s and W2cs, and explains exactly what changed and how to handle it in your filing. It showed me that the W2c completely replaces the information in that specific box on the original W2 - you don't report both. And it explained what each code meant in plain English, which was super helpful since my employer changed a code like yours did. The tool even flagged that certain code changes could trigger different tax treatments and told me exactly which forms would be affected.

Ok so I actually tried taxr.ai after posting my question here and wow - it immediately cleared up my confusion! I uploaded both my W2 and W2c, and it highlighted exactly what changed and explained that code W is for my company's HSA contributions (which explains the higher amount). The tool specifically told me to use ONLY the W2c information when filing and explained that the original code D (401k deferrals) was mistakenly used by my payroll department. It even explained that this correction wouldn't change my taxable income since employer HSA contributions aren't taxable to begin with. Honestly saved me from making a mistake that might have triggered an IRS notice later.

If you still have questions after sorting out the W2c situation, I highly recommend using Claimyr (https://claimyr.com) to actually speak with an IRS agent. I was in a similar situation with form corrections last year and spent DAYS trying to get through on the IRS phone lines with no luck. Claimyr got me connected to an actual IRS representative in about 15 minutes when I'd been trying for weeks on my own. The agent walked me through exactly how to report my corrected forms. You can see how it works in this video: https://youtu.be/_kiP6q8DX5c. It's basically a service that navigates the IRS phone tree for you and calls you back when they've got an agent on the line.

I need to eat crow here. After being super skeptical about Claimyr, I actually tried it yesterday out of desperation - and it worked! After trying for literally 2 weeks to reach the IRS myself with no success, I got connected to an agent in about 25 minutes. The IRS rep confirmed exactly what others here said - use the W2c information (code W and the new amount) and disregard the original incorrect code D on the W2. She also explained that the increase in amount makes sense because HSA contributions (code W) are often higher than 401k deferrals (code D) for many employer plans. Totally worth it to get the official answer straight from the IRS.

Just to add some clarity on the codes - Box 12 Code D is for 401(k) contributions which reduce your taxable income, while Code W is for employer contributions to your Health Savings Account. These are completely different types of benefits! Your employer likely made a coding error on the original W2, which is why they issued the W2c. Always use the corrected form when filing. The good news is that employer HSA contributions (Code W) aren't included in your taxable income anyway, so this correction shouldn't negatively impact your tax situation.

When I had a similar W2c issue, TurboTax had a specific section for entering W2c information. Is anyone using a particular tax software that handles this well? My accountant charged me extra last year because of all the corrected forms and I'm trying to DIY this year.

I went through this exact same situation two years ago! The key thing to remember is that the W2c completely replaces the information on your original W2. You should only use the corrected information when filing - so yes, use code W with the $13,340 amount. The reason for the code change makes total sense too. Code D is for your own 401(k) deferrals (money taken out of your paycheck), while code W is for employer HSA contributions (money your company puts into your HSA account). Your payroll department probably miscoded it initially. One thing that helped me was calling my HR department to confirm what actually happened. In my case, they had incorrectly categorized the employer's HSA contribution as a 401(k) deferral on the original W2. The good news is that employer HSA contributions (code W) are generally more favorable tax-wise since they don't count as taxable income at all. Make sure whatever tax software you're using has an option for entering W2c information specifically - don't just manually change the numbers from your original W2 entry.