For three years, keep copies of your tax returns and accompanying documents. Many people mistakenly believe that as long as they retain their records on hand for three years, they have complied with the record retention requirement and are safe. However, if the IRS believes you have grossly underreported your income (by 25% or more) or that there may be indications of fraud, it may conduct an audit going back six years. Create a backup set of documents and save them electronically. Now that financial institutions give statements and papers electronically and a lot of financial information is available online, keeping a backup set of records is easier than ever. Bank statements, tax returns, insurance policies, and other types of records are examples of this.
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