We are structuring an installment sale under Section 453 with a $7 million seller note to defer capital gains, but our deal team warned us about the Section 453A interest charge on deferred tax liabilities exceeding $5 million. How does this rule work, and how do we structure the notes to minimize this phantom interest penalty?

Question

Tyler Smith · Accepted Answer

Section 453 allows business owners to defer capital gains taxes over the life of a promissory note by recognizing income only as cash payments are received. However, Section 453A imposes a mandatory interest charge on the deferred tax liability if the total face value of all installment obligations arising during the taxable year exceeds $5 million.

This is effectively a phantom interest fee paid directly to the IRS. The government calculates the interest based on the statutory underpayment rate applied to the deferred tax on the note balance exceeding $5 million. If you hold a $7 million installment note, that interest charge applies annually to the deferred tax on the $2 million excess until the principal is paid down.

To minimize or eliminate this drag, work with your transaction tax counsel during the Letter of Intent phase to evaluate these structural remedies:

- Split ownership notes. If the business is owned equally by two or more distinct legal partners or spouses who hold their stock individually, each taxpayer generally receives their own independent $5 million threshold under Section 453A. Splitting the seller note appropriately across qualifying owners can eliminate the penalty entirely.
- Shift the capital stack. Reduce the note face value to exactly $5 million to remain completely under the statutory threshold, and bridge the remaining $2 million through other deal consideration, such as rollover equity, an earnout structured under contingent payment installment rules, or cash funded at close.

Run the cash flow numbers during an offsite strategy session before signing the definitive agreement so you do not get surprised by unexpected federal tax bills.