Did you have to file an amended return (1040-X) along with the 8949 forms when responding to the CP2000? I'm confused about whether I need to redo my whole tax return or just submit the missing forms.

You generally don't need to file a 1040-X when responding to a CP2000 notice. The CP2000 is just a proposed adjustment, not a final determination. You only need to submit the missing or corrected forms (in this case Form 8949 and Schedule D) along with your response to the notice. The IRS will recalculate your tax based on the information you provide. If they accept your explanation and documentation, they'll either send you a corrected CP2000 or a "no change" letter. Only if you discover additional issues not related to what the CP2000 mentions would you need to file an amended return separately.

Wait this is really helpful. I got a 1099-K from my exchange, not a 1099-B. Which box would I check then? Does that count as "not reported to the IRS"?

If you received a 1099-K, then your basis wasn't reported to the IRS. A 1099-K only shows the gross proceeds (total amount of sales) but doesn't include your cost basis information. In this case, you would check Box C for short-term transactions or Box F for long-term transactions since basis was not reported to the IRS. And you'll need to be extra careful to document your cost basis for each transaction, as that's what the IRS is likely questioning on your CP2000 notice.

I'm confused about the home office deduction. I've been working fully remote since 2021 but my employer doesn't require it. Can I still claim my spare bedroom that I use as an office?

Unfortunately, if you're a W-2 employee (even if fully remote), the home office deduction typically isn't available to you anymore. This was suspended by the Tax Cuts and Jobs Act through 2025 for employees. The home office deduction is generally only available if you're self-employed or an independent contractor. If you have a side gig that you run from home in addition to your regular job, you might be able to claim the deduction for that portion of your work, but not for your primary employment.

That's probably for the landlord to complete, not you as the tenant. Some cities in California have rental registry programs where landlords have to register their rental properties and provide information about rent amounts, but those aren't tax forms for renters.

But wouldn't they still have to pay self-employment tax too? Even with $40k net income, shouldn't that be more than $4k total tax between income tax and SE tax?

You're absolutely right about self-employment tax. Even with $40k net income, they would owe about 15.3% in self-employment tax alone, which would be around $6,120. Then they'd still owe some amount of income tax on top of that, even after taking the standard deduction.

That's a great point. For 2023, self-employed individuals could contribute up to $66,000 to a Solo 401(k) if they're under 50. Add in a maxed HSA contribution and some business expenses, and you could bring that taxable income way down legitimately.

Is there a cutoff for how far back you can claim refunds? I haven't filed for 6 years but had withholding the whole time.

Yes, there is a cutoff - it's 3 years from the original due date of the return. So for example, 2022 tax returns were due April 18, 2023, meaning you have until April 18, 2026 to claim any refund for that year. For 2021 returns, you have until April 15, 2025. Unfortunately for your situation with 6 unfiled years, you've likely lost the ability to claim refunds for the oldest 3 years, but you can still get refunds for the most recent 3 tax years if you're owed them.

This is 100% accurate. I work at a tax resolution firm and we help people with 10+ years of unfiled returns regularly. The IRS is far more reasonable than people think as long as you're making an effort to comply. They're not interested in sending people with regular jobs to prison.

That's a good idea! I didn't even think to check my spam folder. I just found the notification email from February 1st buried in there. Clicked the link and got my form downloaded right away. Thanks everyone for the help! Between checking my spam folder and learning about those services if I need them in the future, this has been super helpful.

This is what I had to do last year. The transcript doesn't give you the actual form but at least tells you the amount and who reported it, which you can use on your tax return. The IRS "Get Transcript" online service is faster than mailing the form if you can verify your identity.

Good point about the online Get Transcript service being faster. I always forget that's an option since I had trouble verifying my identity in their system. The transcript does give you the box 1 amount (gross distribution) which is often all you need for basic tax filing if you know the distribution code. But you're right that it's not a replacement for the actual form if you need all the detailed breakdown.