How Do I Know If My Tax Return Has Been Flagged?

So you filed your taxes, hit submit, and now you’re left wondering: Is my tax return sitting under a microscope at the IRS right now? Most people won’t get a knock at their door, but there are warning signs that your return might have hit a snag.

If you suddenly get a letter from the IRS that isn’t just a refund update but asks for extra forms, explanations, or documents, that’s usually the first red flag. Sometimes your refund status will get stuck on “processing” for ages—way longer than the usual three weeks. That’s a hint your return might be under review. And if you log in to your IRS account and see a message about a “review” or “correspondence audit,” well, that’s a pretty loud alarm bell.

It’s not always bad news, but you need to pay attention. Being flagged doesn’t mean you did something wrong, but ignoring those signs won’t make the IRS go away. If you’re wondering about the next steps or why the IRS even picked your return, keep reading—you’ll get some straight answers and helpful moves you can make right now.

• The Telltale Signs Your Return Is Flagged
• Common Reasons Returns Get Flagged
• How to Check the Status of Your Return
• What Happens Next if You’re Flagged?
• How to Avoid Getting Flagged in the Future

The Telltale Signs Your Return Is Flagged

Ever notice your tax refund is just stuck in limbo? That’s not a great sign. If it feels like everyone around you already got their refund and you’re still seeing “Your return is being processed,” you might want to buckle up. An unusually long wait, especially if it drags past 21 days, can mean the IRS has pulled your tax return for a closer look.

The most obvious heads-up is getting a letter from the IRS. We’re not talking about the standard "Here’s your refund" note, but something asking for extra details—maybe proof of income, W-2 forms, or your 1099. These letters might use words like “under review,” “correspondence audit,” or ask you to send more info. Pay attention to the codes in these letters, like 4464C (review notice) or 4883C (identity verification). The letters always arrive by mail, so if you get an IRS email, it’s probably a scam.

You can also get clues by checking your IRS online account or the "Where’s My Refund?" tracker. If there’s a message about delays, review, or the need for more info, the IRS definitely put your return aside for a second look. Sometimes, they’ll freeze your refund while checking things out, which can really drag things out for months.

• tax return flagged usually means they spotted something that doesn’t quite match up—like a big jump in income or a mismatch between reported earnings and what your employer reported.
• If you see IRS transcript codes like 570 (Additional Action Pending) or 971 (Notice Issued), those can be a dead giveaway.

To give you a real sense of the numbers, here’s how often the IRS actually flags returns (based on recent public data):

So, most people don’t get flagged. But if you’re one of the few, the signs are usually easy to spot—if you know what to look for and act fast when you see them, you’ll save yourself a world of hassle.

Common Reasons Returns Get Flagged

Most flagged tax returns set off the IRS’s radar because of a few classic mistakes or red flags. The IRS uses both real people and computer systems to check returns that look odd compared to the millions they see every year. Here’s the stuff that usually gets attention.

• Math errors and typos. Simple addition mistakes, numbers that don’t match up, or mixing up Social Security numbers can freeze your refund. Computers catch these fast.
• Missing income. If you forgot a W-2, a freelance 1099, or any kind of tax form that the IRS already received from your employer, bank, or gig app, your return is flagged almost instantly.
• Big jumps in income or deductions. Say you normally make $50K, but this year you claim $100K, or your deductions suddenly double. The IRS will want to know what changed.
• Unusual credits or big refunds. Trying to claim a credit you normally don’t qualify for, or getting a refund that’s much higher than usual, often sets off the system for a closer look.
• Self-employment and cash income. Self-employed people and those who report cash tips or gig earnings always get a little more attention, especially if their expenses seem too high for their type of work.
• Claiming dependents that don’t match IRS records. If you list a dependent who someone else also lists, or if info doesn’t line up with the IRS database, expect a follow-up.

Want some numbers? Here’s a quick look at recent IRS audit and flagging data:

*Estimated based on audits and correspondence reviews from IRS data (2023–2024)

It’s not random, and the IRS isn’t out to get you—but their algorithms are tuned to sniff out returns that break patterns. If your return gets flagged, it’s all about the numbers not lining up or looking out of the ordinary compared to others in your bracket or industry.

How to Check the Status of Your Return

When you’re anxious about where your tax return stands, there are a few ways to get real answers—some quicker than others.

The fastest way to see what’s up with your return is to use the IRS “Where’s My Refund?” tool. You’ll find it on the IRS.gov homepage, and you just need your Social Security number, filing status, and the exact amount of your refund. This online tracker updates once a day, usually overnight. If your status gets stuck at “processing” for more than 21 days, or if you see any unusual messages about delays or extra review, that’s a big hint your return’s being checked more closely.

If you filed a paper return, heads up—it takes way longer. You might be left hanging for weeks, sometimes even two months, before you see any kind of update. If you’re desperate for info, you can call the IRS directly at 1-800-829-1040, but be ready for a wait. You’ll need your Social Security number, filing status, and details from your last return. IRS reps won’t give you juicy details about what’s wrong, but they can confirm if your return is under review or needs more info.

• tax return flagged cases often start with a letter. The IRS almost always sends an official notice by mail if there’s an issue—never by phone or email first. Watch for forms like 5071C, 4883C, or 4464C. These usually mean your return got snagged because something didn’t add up, or more proof is needed.
• If you set up an online IRS account, you can check your transcript. If you spot transcript codes like 570 (Hold) or 971 (Notice Issued), your return is getting a closer look.

Here’s a quick look at how long things usually take and what different statuses mean:

If you don’t get an answer within a month or you see a letter about a review, act fast. Respond to the IRS right away and keep copies of anything you send. Staying on top of your status is the best way to avoid nasty surprises down the road.

What Happens Next if You’re Flagged?

Once the IRS flags your return, things change gears. You won’t get a phone call out of nowhere—first contact almost always comes as a letter through regular mail. This official notice spells out if you’re just under extra review or if they're moving forward with an audit. Read that letter carefully; skimming it could cost you time, headaches, or even money.

The letter usually tells you what’s raising eyebrows: maybe your reported income doesn’t match what an employer sent in, a credit claim looks odd, or some documents are missing. Don’t ignore deadlines in the notice—if you do, the IRS could adjust your tax return without your side of the story, and you’ll likely lose out.

• Respond on time: Most letters give you 30 days to send in extra info. Keep it quick and complete.
• Gather records: Find your W-2s, 1099s, receipts, or whatever proof matches what’s questioned.
• Follow instructions: Mail or upload the documents exactly as explained in the letter.
• If you get stuck: Call the IRS number listed or consider getting help from a tax pro, especially if things get complicated.

When you respond fast and with everything the IRS asks for, many reviews wrap up without much fuss. But sometimes, the IRS will move you to a full-on audit, which can happen by mail or in person. Mail audits are most common—over 70% of all audits happen this way. In 2022, out of over 160 million returns, less than 0.4% were audited, and most involved simple follow-ups, not sit-down meetings.

Remember, a flagged return doesn’t mean jail or massive fines. It means your return stands out for some reason. Play it straight, respond timely, and keep all your records. If you stay on top of things, you can smooth out most hiccups before they turn into bigger problems. And if you’re ever unsure, the IRS account portal updates your status and shows what’s next, so check there regularly. That’s how you stay ahead when your tax return flagged nightmare starts to play out.

How to Avoid Getting Flagged in the Future

No one wants their tax return flagged by the IRS, but you can do a lot to lower your chances. The system that screens returns—called the IRS Automated Underreporter—hunts for mismatches and weird patterns, so the first step is making sure all your numbers check out.

Double-check that every form you get (W-2s, 1099s, etc.) matches up exactly with what you file. Even a tiny typo or missed decimal will set off their system. Another classic mistake? Rounding all your figures. If your numbers end in zeroes across the board, it looks suspicious. Use the exact amounts listed—don't guess or estimate.

Claiming big deductions or credits you can't back up is another common reason to get flagged. Home office deductions? Business expenses? You need receipts and solid records to prove every claim. The same thing goes for charitable donations. If you’re giving a big chunk to charity, keep your paperwork handy.

Here are a few tips that can keep you out of the IRS’s sights:

• File electronically. E-filing helps avoid mistakes and is processed faster, plus it gives you an immediate confirmation.
• Don’t rush. Take your time to review everything, especially your Social Security Number and banking info.
• Report all your income, not just what you remember off the top of your head. The IRS gets copies of every form you get.
• If you’re self-employed, keep tight records. Use a bookkeeping app or a spreadsheet—just stay organized.
• Avoid sketchy tax preparers who make wild promises. Their “magic” deductions usually end up getting flagged, too.

If something on your return is unusual, the best move is to attach an explanation or statement. This heads off questions, shows you’re not hiding, and helps the IRS understand what’s up. Following these steps doesn’t guarantee you’ll never be flagged, but it seriously cuts down the chances you'll hear back from the IRS for the wrong reasons.