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Anyone making less than $66,000 a year can file their taxes for free. Oftentimes, that's easier said than done.

Intuit, which makes TurboTax, makes it difficult for people to find the free option, according to ProPublica. Instead, searches on terms such as "irs free file taxes" steer potential tax filers to for-pay versions of its service, according to the publication.

Intuit, along with H&R Block, has lobbied for years to prevent the Internal Revenue Service from building its own free online tax filing system because it would compete with their products, according to ProPublica. Members of Congress pushed to prevent the IRS from offering free online filing as recently as this month, the publication reported.

The IRS has agreed not to make online tax filing free as long as tax-preparation companies, who have formed an industry group called the Free File Alliance, provide free services to taxpayers making less than $66,000. Locating Intuit's free service, however, requires a lot of work, according to ProPublica.

ProPublica went to Intuit's TurboTax website and clicked on the "FREE Guaranteed" option but was tagged as a potential paying customer. The reason: Intuit doesn't offer its free version from its website, ProPublica said.

ProPublica discovered the free version for filers with less than $66,000 in income is called the Freedom Edition. Once the publication had that information, a Google search brought up the right result. But the Intuit site still tried to channel ProPublica back to a for-pay version, it said. Clicking on a link titled "Start for Free" on the page led to a for-pay version of TurboTax, while clicking on "See If You Qualify" led to the actual free filing option.

TurboTax also offers a product called Free Edition, a no-cost version for users with simple filings. Eligibility for Free Edition isn't based on income, but rather on filing circumstance, such as W2, standard deduction and child tax credits.

TurboTax spokesman Rick Heineman said pricing for TurboTax products is listed on the company's Products & Pricing page. "This information is made clear to customers before they begin to file," he wrote.

TurboTax Free File Program, which is on a page whose URL reads https://turbotax.intuit.com/taxfreedom/, is the Intuit product used as part of the income-based IRS Free File. Heineman said the TurboTax Free File Program "contains no cross-marketing or selling of ancillary products or services."