16 I did that last year and it was a huge pain. Had to file amended returns for both federal and state, which meant more forms, more waiting, and more stress. Plus, if you owe additional tax because of the correction, you might get hit with interest and penalties for the underpayment. If you can get the W-2c directly from your employer (which they should provide), I'd recommend waiting and filing correctly the first time. The October 15 extension deadline still gives you some time.

I use TurboTax and it actually asks you to enter both Box 1 and Box 2a separately. If you've been entering both correctly, it should be using the Box 2a amount as your taxable income. But if you've only been entering Box 1 or didn't understand what it was asking, then you might have the same issue as OP.

4 Do TSA contributions count toward the limits of traditional IRA contributions? I'm already maxing out my Roth IRA but still trying to save more for retirement while fixing this tax issue.

22 No, they're completely separate limits. Your 403(b)/TSA contribution limit for 2025 is $23,500 (plus catch-up contributions if you're over 50), while your IRA limit is $7,000. You can max out both if you can afford it. The nice thing for teachers is that many districts offer both 403(b) and 457(b) plans, and you can contribute the maximum to EACH plan, potentially sheltering over $47,000 from taxes if you maxed both. Most teachers don't come close to that, but even increasing your contributions by a few percent can make a big difference in your tax situation.

17 I use it every January and then again in June to double-check. It's surprisingly accurate! You need your most recent paystubs and last year's tax return handy. Takes about 15 minutes but gives you the exact dollar amount to put on line 4(c) of your W-4 for additional withholding. Saved us from owing for the first time in 5 years of teaching.

The IRS Withholding Estimator is definitely the way to go! I wish I'd known about it years ago. As a new teacher, I was just guessing at how much extra to withhold and still ended up owing. The estimator asks for specific details about both spouses' income, deductions, and filing status. It even accounts for things like the educator expense deduction automatically if you input that you're a teacher. The key is to run it at the beginning of the year and then again mid-year if anything changes with your income or deductions.

Do you know if these state sites would show investment accounts too? Or just W-2 type employment stuff? I'm particularly worried about tracking down all my stock trades.

State sites vary widely in what they show. Most focus primarily on W-2 income since that's what affects state income tax most directly. Investment accounts and 1099-B information are less consistently tracked at the state level. For stock trades specifically, you might be better off requesting your "Account Transcript" from the IRS in addition to the Wage and Income Transcript. Sometimes brokerage reporting shows up there even before the detailed 1099 information is fully processed. Also consider checking the mail forwarding settings on all your accounts - I've missed tax forms simply because they went to an old address.

How far back can you go with these transcripts? I'm worried about stuff from like 3-4 years ago too.

You can go back up to 10 years with IRS transcripts! Both the Wage and Income Transcript and Account Transcript are available for the current year plus the previous 10 tax years. So if you're worried about 2020-2021, you're definitely still within the window to request those. The Account Transcript is particularly useful for older years because it shows any automated adjustments the IRS made to your account, which often happens when they receive income forms that weren't on your original return. If there were discrepancies 3-4 years ago, they would likely show up there as CP2000 notices or other correspondence.

This is an important distinction! The "hobby loss rule" means you can't deduct losses from a hobby against other income. If the IRS determines your activity is a hobby rather than a business, you still report the income but can only deduct expenses up to the amount of income (not below zero).

Great question! By "consistent" I mean using the same methodology across similar items - you don't have to use eBay for everything, but if you use eBay sold listings for one Pokemon card from 2019, you should generally use that same approach for other Pokemon cards from that era rather than switching to price guides that might show different values. You absolutely can go back 5+ years - in fact, that's often when you'll see the biggest difference between purchase price and current values, which helps demonstrate legitimate losses. For older items, try to find data points as close to your actual purchase date as possible. Archive.org sometimes has snapshots of old price guide websites, and some auction houses keep historical records. The key is showing you made a reasonable, good-faith effort to determine what you actually paid. Document your research process - save screenshots of the eBay sold listings you used, note the dates and sources. If an auditor questions it, you can show exactly how you arrived at your numbers.

Good question! By "consistent" I mean using a reasonable and systematic approach rather than cherry-picking. You don't have to use the exact same source for every item, but your methodology should be defensible. For example, using eBay sold listings for most items but switching to a price guide for rare items where sales data is sparse is fine. For the timeframe, 5+ years is definitely doable. I've successfully documented items going back 6-7 years using archived price data. The key is showing you made a good-faith effort to find contemporaneous market values. Archive.org can be helpful for accessing old price guide websites, and some auction houses maintain searchable databases of past sales. One tip: document your research process! Keep notes on which sources you used and why. If questioned, being able to show you used multiple data points and took a conservative approach goes a long way with the IRS.