NOTICE FOR MARCH 3-4, 2025: CFMA accounts will be inaccessible from 8 AM ET on March 3, 2025, through 8 AM ET on March 4, 2025, for maintenance. This may impact access to renew or join CFMA, Connection Café, CFMA's 2025 Annual Conference registration, BP Online, CFMA education, etc. Thank you for your patience, and please contact info@cfma.org with any questions.

Converting from a C to an S Corporation? Beware the Built-in Gains Tax

To avoid double taxation, a C corporation may consider converting to an S corporation. However, when the fair value of an entity’s assets at the relevant date of conversion is more than its tax basis, a C corporation may incur the built-in gains tax,1 which applies to certain assets that have appreciated or are converted to cash after a C corporation changes to an S corporation.2

This extra tax can surprise “converting” businesses, especially contractors that use a more favorable revenue recognition method for tax purposes, such as the cash basis or completed-contract method (CCM). Let’s look at the nuances that affect the built-in gains tax.

Impact of Deferred Income & Other Attributes

The unrecognized built-in gains at the time of conversion is not just the unrecognized gain on the sale of appreciated assets. The built-in gains tax is also impacted by deferred income.

Deferred Income Example

Let’s assume that a contractor converted from C corporation to S corporation status during 2016. At the time of conversion, the contractor has four contracts in progress, on which $1 million of gross profit would be recognized if the percentage-of-completion method (PCM) had been used.

However, the contractor qualifies for exemption from IRC § 460 under the small contractor’s exemption and uses the CCM.3 The calculation at right shows what taxes would be due if all four contracts were completed during 2017.4

The S corporation and its shareholders pay $607,400 of total tax: $350,000 at the corporate level and another $257,400 at the shareholder level. This represents an effective rate of more than 57% on the $1 million of unrecognized contract profits as of the date of conversion to S corporation status. The effective rate may be even higher if state income taxes are applicable.

If you are a CFMA member login to continue reading this article. If you aren't a member yet and would like unlimited access to all of the content on cfma.org, plus a variety of other benefits, join CFMA today!

About the Author

Rich Shavell

Read full bio