(CNN) -- Taxpayers should be on alert for identity thieves, e-mails falsely claiming to be from the IRS and shady tax preparers this year, the IRS warns.
These are a few of the tax scams that commonly pop up during tax season, as highlighted in the annual "dirty dozen" list the agency released Tuesday.
12 tax audit red flags
12 tax audit red flags
To avoid catching the attention of the IRS, beware of these pitfalls.
"Don't let a scam artist steal from you or talk you into doing something you will regret later," said IRS acting commissioner Steven Miller.
Here are 12 schemes to beware of:
1. Identity theft
Identity thieves are increasingly getting hold of taxpayers' names, Social Security numbers, birth dates and other information, then fraudulently claiming tax refunds in their names.
In response, the IRS has been updating its fraud screening systems and penalizing more identity thieves. Last year, the agency stopped $20 billion in fraudulent refunds from being issued -- up from $14 billion in 2011. And earlier this year, it launched a nationwide crackdown that brought enforcement actions against 389 identity theft suspects in 32 states. The IRS has also more than doubled its staff devoted to identity theft cases.
Related: 12 tax audit red flags
If you get a notice from the agency that more than one return has been filed under your name, it may mean your identity has been compromised. If you suspect that's the case, contact the IRS Identity Protection Specialized Unit at 1-800-908-4490. And if you are in fact a victim, expect a longer wait for your refund.
Have you received an e-mail that appears to be from the IRS? It's probably not. Instead, it could be from a scammer who will try to use any information you reply with to steal your identity and money. The IRS does not use e-mail, texts or social media to contact taxpayers for personal or financial information, so relay any such messages to email@example.com.
3. Fraudulent tax preparers
When choosing a preparer, make sure he or she has an IRS Preparer Tax Identification Number (PTIN). If a preparer doesn't put this number on your tax return as required, or fails to sign the form, that should raise a red flag. And watch out for preparers who base fees on the size of your refund or promise refunds that sound too good to be true.
Complaints about shady tax preparers can be submitted via Form 14157.
4. Illegal offshore bank accounts
The IRS has been cracking down on taxpayers illegally hiding income abroad. Launched in 2009, the agency's voluntary disclosure program has already raked in $5.5 billion in back taxes, interest and penalties from tax cheats for illegally hiding assets in offshore accounts.
Related: 12 ways to save on your taxes
If you have a legitimate account abroad, you won't get in trouble if you properly complete the reporting requirements. But by failing to disclose assets held in offshore accounts, you risk huge penalties -- including a fine of $100,000 or 50% of the account balance, whichever amount is greater.
5. Promises of 'free money'
Be skeptical of flyers and advertisements promising you "free money" from the IRS. Scammers have been targeting low-income and elderly people, often through community churches, convincing them to claim credits they aren't entitled to -- and even Social Security rebates that don't exist.
These con artists often charge up-front fees and disappear without a trace before the claims are rejected by the IRS. And along with losing whatever they gave the scammer, victims could also end up owing the IRS a hefty $5,000 penalty for making intentional errors on their return.