Just curious - roughly how much money are we talking about here? Like is this a few hundred dollars difference in the credit or thousands? I'm wondering because the level of concern probably should match the scale of the issue.

I really appreciate everyone sharing their experiences here. As someone who went through a similar correction process a few years ago, I want to emphasize that the IRS actually has clear guidance for situations exactly like this. The key distinction is between "mistake" and "fraud" - fraud requires intent. When you filed based on documentation provided by your daycare, you had no intent to deceive. The fact that you're coming forward voluntarily after discovering the error actually works strongly in your favor. For a $2,800 difference, definitely file the amended return with a clear explanation. I'd suggest wording it something like: "Amended to correct child care credit amount based on actual payments made. Original filing was based on documentation provided by childcare provider that was later discovered to be incorrect. Taxpayer is voluntarily correcting upon discovery of discrepancy." Include your actual receipts/bank statements showing what you paid, and file as soon as possible. The IRS generally views voluntary corrections very favorably, especially when you're paying additional tax owed. You'll likely just pay the difference plus interest - penalties are uncommon for good faith corrections. Don't let anxiety keep you from sleep over this. You're handling it exactly the right way.

Thanks everyone for all the helpful advice! I found my Copy B - it was clearly labeled "To Be Filed With Employee's FEDERAL Tax Return" just like Chloe mentioned. I was overthinking it way too much. For anyone else confused like I was, here's what I learned: Look for the specific Copy B section on your W-2 (it's usually perforated so you can tear it off cleanly), attach it to the front of your 1040 with a small paper clip (not staples!), and make sure you're mailing to the right IRS processing center for your state. I'm getting this in the mail tomorrow so I can stop stressing about the deadline. Really appreciate this community helping out a tax newbie!

Great advice from everyone here! As someone who's been filing paper returns for years, I can confirm that Copy B is absolutely required for federal returns. One additional tip - if you have multiple W-2s from different employers, make sure to attach ALL of the Copy B forms. I made that mistake once and had to mail in the missing ones separately, which delayed my processing. Also, double-check that all the information on your W-2 matches what you entered on your 1040. Even small typos in names or amounts can cause issues. The IRS computers are pretty good at catching discrepancies between what you report and what your employer reported. Good luck getting that return in the mail on time!

Day 23 still nothing... IRS playing hide and seek with these letters fr

I'm on week 3 waiting for mine too! Called the 800-830-5084 number yesterday and they said if it's been more than 4 weeks you can request they send another one. The rep also mentioned checking your online IRS account to see if there's an option to verify through ID.me instead of waiting for the letter. Might be worth looking into if you're getting anxious about the wait like I am!

This W4 Box 2c confusion is so common! I work as a tax preparer and see this exact scenario multiple times every tax season. You're absolutely right that the mismatch caused your underpayment issue. Here's what happened: When you checked Box 2c, your employer's payroll system adjusted your withholding to account for having two working spouses with similar incomes. But when your husband didn't check it, his employer withheld taxes as if he was the sole breadwinner supporting a non-working spouse - which means much less tax was taken out of his paychecks. For 2026, definitely have your husband submit a new W4 with Box 2c checked. Since you both earn around $65k, this should solve most of the problem. However, I'd also recommend running the numbers through the IRS Tax Withholding Estimator mid-year to make sure you're on track, especially since you mentioned these were new jobs in 2024. One tip: if you want to be extra safe and avoid any surprises, you could have a small additional amount withheld from one of your paychecks using Step 4(c) - maybe $50-100 per month. This creates a small buffer without significantly impacting your monthly budget.

This thread has been incredibly helpful - I had no idea the W4 Box 2c could cause such issues! My partner and I are planning to get married next year and we both work (I make about $58k, they make about $62k). Based on what everyone's shared here, it sounds like we'll need to both check Box 2c when we update our W4s to "married filing jointly" status. But I'm curious - should we wait to make this change until after we're actually married, or can we update our W4s as soon as we know we'll be married for tax purposes? Also, since our incomes are pretty close to what Jacob and his husband earn, would it make sense to also add that small buffer amount in Step 4(c) that Keisha suggested? I'd rather be safe than sorry after reading about everyone's surprise tax bills!

Has anyone here actually used the Schedule E for rental income before? I'm still confused about where to report the income if we do form an LLC. Is it still Schedule E or do we have to use a different form?

Just wanted to add some clarity on the QJV election since there seems to be some confusion in the thread. The Qualified Joint Venture election under Section 761(f) is actually quite specific - it's available to married couples who jointly own an unincorporated business and choose to be treated as a QJV instead of a partnership. The key point is "unincorporated business" - this means no LLC, no corporation, just direct ownership. If you form any type of entity (single-member LLC, multi-member LLC, etc.), you cannot make the QJV election. For your inherited rental property situation, here's what I'd consider: If liability protection is important (which it usually is with rental properties), the LLC route makes sense. A single-member LLC would be disregarded for tax purposes, so you'd report everything on your Schedule E. Your spouse could be involved in management without being a formal member. If you want both spouses to have formal ownership recognition, then a multi-member LLC taxed as a partnership might be better, though it does require filing Form 1065 and issuing K-1s. The QJV election is really more useful for businesses like consulting or other service businesses where spouses want to split self-employment income for Social Security credits, not typically for rental properties.