The standard rule is three years. The IRS has three years from the date you file your return (or the due date, whichever is later) to initiate an audit. So if you filed your 2023 business return on April 15, 2024, the IRS generally has until April 15, 2027 to come knocking. Most audits happen within two years of filing, but they can use the full three-year window.

That three-year window stretches to six years in one important situation. If the IRS determines you understated your gross income by more than 25%, they get double the time. This doesn’t require intentional wrongdoing on your part. Miscategorizing income, missing a 1099 you forgot about, or incorrectly excluding revenue can all push you over that 25% threshold. Six years is a long time to wonder if the IRS is going to review your records.

There is no time limit at all in two scenarios. If you file a fraudulent return or if you never file a return, the statute of limitations never starts running. The IRS can come after you 10 or 15 years later if they discover fraud. And if you skipped filing entirely for a year, there is no deadline for them to assess taxes owed for that period.

What this means practically is that you need to keep your business records for at least seven years. That includes bank statements, receipts, invoices, payroll records, and your tax returns themselves. Many business owners toss records after a year or two and then panic when they receive an audit notice. Digital storage makes this easy. There is no reason to not keep everything backed up and organized.

The quality of your bookkeeping directly affects how stressful an audit becomes. Clean, well-organized books with proper documentation turn an audit into a straightforward process. Messy or incomplete records turn it into a nightmare where the IRS starts making assumptions that usually don’t favor you. Good financial strategy includes maintaining records that can withstand scrutiny years after the fact.

A few other things worth knowing. Filing an amended return can restart the three-year clock for the items you changed. Certain state tax agencies have their own audit windows that may differ from the IRS. And if you sign a consent form agreeing to extend the statute of limitations during an ongoing audit, you’ve given the IRS more time voluntarily. Don’t sign anything without understanding the implications.

If you do receive an audit notice, respond promptly and don’t try to handle it alone. Tax audit support from someone who understands the process can make a significant difference in the outcome. Having a CPA represent you means the IRS deals with a professional who knows what they’re entitled to see and what they’re not, rather than a business owner who might volunteer information that wasn’t even requested.

The best audit strategy is prevention. File accurate returns, keep thorough records, and make sure your books are done right the first time. You can’t control whether the IRS selects you, but you can control how prepared you are if they do.