C-Corporation Sale Tax Planning: Double Tax and QSBS Exclusion

Selling a C-corporation faces double taxation risks, but QSBS exclusion may eliminate federal tax entirely. Understand your options for stock sales and QSBS eligibility.

Double taxation is the core problem. In an asset sale, the corporation pays corporate tax (21%) on the gain, and the remaining proceeds are taxed again as a dividend or liquidating distribution to shareholders. Effective combined rates can exceed 40%. This is why C-corp sellers strongly prefer stock sales.

Stock sales avoid the corporate layer. If the buyer purchases your stock directly, the corporation never recognizes gain. You pay capital gains tax only at the shareholder level. However, most buyers resist stock sales because they inherit all the corporation's liabilities and get no basis step-up on assets.

Section 338 election forces asset sale treatment. A buyer can make a Section 338(g) election to treat their stock purchase as an asset acquisition, giving them a stepped-up basis. But this triggers the double tax to you as if assets were sold. A 338(h)(10) requires agreement from both parties.

QSBS may eliminate shareholder tax entirely. Under Section 1202, if the stock is qualified small business stock -- original issuance of a C-corp with under $50 million in assets, held more than five years -- up to $10 million in gain is excluded from federal tax.

The tradeoff: Stock sales avoid double taxation but are harder to negotiate. Asset sales are buyer-friendly but punishing to sellers. QSBS exclusion is the best outcome but has strict eligibility rules your CPA must verify before you rely on it.