Schedule C is a treasure trove of tax deductions for self-employeds. But it's also a gold mine for IRS agents, who know from experience that self-employeds sometimes claim excessive deductions. History shows that most underreporting of income and overstating of deductions are done by those who are self-employed. And the IRS looks at both higher-grossing sole proprietorships and smaller ones. Big deductions for meals, travel and entertainment are always ripe for audit. A large write-off here will set off alarm bells, especially if the amount seems too high for the business. Agents are on the lookout for personal meals or claims that don't satisfy the strict substantiation rules. To qualify for meal or entertainment deductions, you must keep detailed records that document for each expense the amount, the place, the people attending, the business purpose and the nature of the discussion or meeting. Also, you must keep receipts for expenditures over $75 or for any expense for lodging while traveling away from home. Without proper documentation, your deduction is toast.
7. Claiming 100% business use of a vehicle
Another area ripe for IRS review is use of a business vehicle. When you depreciate a car, you have to list on Form 4562 what percentage of its use during the year was for business. Claiming 100% business use of an automobile is red meat for IRS agents. They know that it's extremely rare for an individual to actually use a vehicle 100% of the time for business, especially if no other vehicle is available for personal use. IRS agents are trained to focus on this issue and will scrutinize your records. Make sure you keep detailed mileage logs and precise calendar entries for the purpose of every road trip. Sloppy recordkeeping makes it easy for the revenue agent to disallow your deduction. As a reminder, if you use the IRS' standard mileage rate, you can't also claim actual expenses for maintenance, insurance and other out-of-pocket costs. The IRS has seen such shenanigans and is on the lookout for more.
8. Writing off a loss for a hobby activity
Your chances of "winning" the audit lottery increase if you have wage income and file a Schedule C with large losses. And if the loss-generating activity sounds like a hobby -- horse breeding, car racing and such -- the IRS pays even more attention. Agents are specially trained to sniff out those who improperly deduct hobby losses. Large Schedule C losses are always audit bait, but reporting losses from activities in which it looks like you're having a good time all but guarantees IRS scrutiny.
You must report any income you earn from a hobby, and you can deduct expenses up to the level of that income. But the law bans writing off losses from a hobby. For you to claim a loss, your activity must be entered into and conducted with the reasonable expectation of making a profit. If your activity generates profit three out of every five years (or two out of seven years for horse breeding), the law presumes that you're in business to make a profit, unless IRS establishes otherwise. If you're audited, the IRS is going to make you prove you have a legitimate business and not a hobby. So make sure you run your activity in a businesslike manner and can provide supporting documents for all expenses.
9. Running a cash business
Small business owners, especially those in cash-intensive businesses -- think taxis, car washes, bars, hair salons, restaurants and the like -- are a tempting target for IRS auditors. Experience shows that those who receive primarily cash are less likely to accurately report all of their taxable income. The IRS has a guide for agents to use when auditing cash-intensive businesses, telling how to interview owners and noting various indicators of unreported income.
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10. Failing to report a foreign bank account
The IRS is intensely interested in people with offshore accounts, especially those in tax havens, and tax authorities have had success getting foreign banks to disclose account information. The IRS has also used voluntary compliance programs to encourage folks with undisclosed foreign accounts to come clean -- in exchange for reduced penalties. The IRS has learned a lot from these programs and has collected a boatload of money.
Failure to report a foreign bank account can lead to severe penalties, and the IRS has made this issue a top priority. Make sure that if you have any such accounts, you properly report them when you file your return.
11. Engaging in currency transactions
The IRS gets many reports of cash transactions in excess of $10,000 involving banks, casinos, car dealers and other businesses, plus suspicious-activity reports from banks and disclosures of foreign accounts. A report by Treasury inspectors concluded that these currency transaction reports are a valuable source of audit leads for sniffing out unreported income. The IRS agrees, and it will make greater use of these forms in its audit process. So if you make large cash purchases or deposits, be prepared for IRS scrutiny. Also, be aware that banks and other institutions file reports on suspicious activities that appear to avoid the currency transaction rules (such as persons depositing $9,500 in cash one day and an additional $9,500 in cash two days later).
12. Taking higher-than-average deductions
If deductions on your return are disproportionately large compared with your income, the IRS may pull your return for review. But if you have the proper documentation for your deduction, don't be afraid to claim it. There's no reason to ever pay the IRS more tax than you actually owe.