What Is the S Corp AAA and How Does It Work?

The S corp AAA, or Accumulated Adjustments Account, is a corporate-level running total that tracks how much of an S corporation’s income has already been taxed at the shareholder level but not yet distributed. Its job is narrow but important: when an S corporation that used to be a C corporation pays out cash or property, the AAA decides how much of that distribution comes out tax-free and how much is taxed as a dividend from old C corporation earnings.¹

What the AAA Tracks

The AAA is a single account kept on the corporation’s books, not divided among individual shareholders. It starts at zero on the first day of the corporation’s first tax year as an S corporation and adjusts annually for the income, losses, deductions, and non-deductible expenses that flow through to owners. Each year it’s reported on Schedule M-2 of Form 1120-S, which reconciles the beginning-of-year balance to the end-of-year balance.¹

Think of it as a pool of already-taxed dollars sitting inside the corporation. Shareholders reported the income on their personal returns when it passed through on their K-1s; the AAA records how much of that income the corporation still holds. When cash later goes out the door, the AAA tells you whether those dollars come out tax-free (because they were already taxed) or as a taxable dividend (because they trace back to old C corporation earnings).

One important exclusion: tax-exempt income and the expenses tied to it are kept out of the AAA entirely. Items like tax-exempt interest go into a separate account called the Other Adjustments Account (OAA).²

Who Actually Needs to Care About the AAA

If your corporation has always been an S corp and never absorbed C corporation assets, it has no accumulated earnings and profits (AEP). In that case, distributions are simple: each one reduces the shareholder’s stock basis, and anything above basis is capital gain. The AAA doesn’t technically drive the tax result.²

Even so, the IRS instructions for Form 1120-S recommend maintaining the AAA anyway. If the corporation later merges with an entity carrying AEP, you’ll need to reconstruct the AAA at the time of that transaction, and rebuilding years of history after the fact is far harder than keeping the account current.¹

What Increases and Decreases the AAA

The AAA adjustments mirror most of the same items that adjust a shareholder’s stock basis under Section 1367, with the difference that tax-exempt income and its related expenses are excluded.³

The AAA goes up by the corporation’s taxable income items for the year. That includes separately stated items like capital gains, interest, and rental income, along with non-separately computed ordinary business income. It goes down by separately stated losses and deductions, non-separately computed losses, and non-deductible expenses that aren’t related to tax-exempt income. Common non-deductible items that reduce the AAA include life insurance premiums where the corporation is the beneficiary and the reduction in research expenditures required when claiming the research credit.⁴ Federal taxes carried over from C corporation years do not reduce the AAA.³

The Annual Ordering Rules

Adjustments must be applied in a specific sequence each tax year:

Increase the AAA for all income items.
Decrease it for deductible losses, non-deductible expenses, and depletion, but check for a net negative adjustment first.
Decrease it for non-dividend distributions, but not below zero.
Apply any net negative adjustment last.

The net negative adjustment rule is where this gets tricky. If total decreases from losses and expenses exceed total increases from income, the excess is a “net negative adjustment.” When that happens, you skip the net negative adjustment in the expense step and apply it only after distributions have already reduced the AAA. In a loss year, distributions come out of whatever positive AAA existed before the loss hits, which can allow more tax-free distributions than you’d expect.¹

Distributions can never push the AAA below zero. Only losses, deductions, and non-deductible expenses can create a negative balance. That negative balance carries forward and must be absorbed by future income before the corporation has positive AAA available to source tax-free distributions again.³

How a Distribution Gets Sourced When AEP Exists

When an S corporation carries AEP from its C corporation days, Section 1368(c) sets an ordering system that decides whether each dollar distributed is tax-free or taxable. The full sequence:⁵

AAA first. To the extent the distribution doesn’t exceed the shareholder’s stock basis, it’s tax-free. Anything above basis is capital gain.
Previously Taxed Income (PTI), if any remains from pre-1983 S corporation years. PTI is shareholder-specific and doesn’t transfer between owners; very few corporations still carry a PTI balance.
Accumulated Earnings and Profits. Once the AAA and PTI are exhausted, distributions are taxable dividends to the extent of remaining AEP.
Other Adjustments Account and remaining basis. After AEP is zeroed out, distributions come from the OAA and then reduce the shareholder’s remaining stock basis tax-free.
Excess over basis is gain from the sale of stock, typically capital gain.

The critical point: the AAA acts as a shield. As long as it has a positive balance, distributions stay tax-free up to the shareholder’s basis. Once the shield is gone, distributions hit the AEP layer and become taxable dividends.²

AAA Versus Shareholder Stock Basis

The AAA and stock basis sound similar because many of the same items adjust both, but they serve different purposes, and confusing them is a reliable way to get distributions wrong.

The AAA is a single corporate-level account shared across all shareholders. It answers one question: how much of the corporation’s undistributed income has already been taxed? Stock basis, by contrast, belongs to each individual shareholder and measures their total investment, including contributions, loans, and their share of income and loss. Basis limits how much loss a shareholder can deduct and how much distribution they can receive before recognizing gain.

Most items move both accounts the same direction. Ordinary business income increases the AAA and each shareholder’s basis proportionally; losses reduce both. Several items create divergence:

Tax-exempt income increases stock basis but does not increase the AAA. It goes to the OAA.
A distribution treated as a taxable dividend from AEP does not reduce the AAA (it wasn’t sourced from there), but it still reduces the shareholder’s stock basis.
Capital contributions and shareholder loans increase basis but have no effect on the AAA.

A shareholder can have a stock basis well above the AAA (because they contributed capital) or well below it (because they took prior distributions that reduced basis). The taxability of a distribution depends on the corporate-level AAA ordering, while the tax-free ceiling for any individual shareholder depends on their personal basis.²

Property Distributions

When an S corporation distributes property instead of cash, the AAA consequences depend on whether the property has appreciated or depreciated. If fair market value exceeds tax basis, the corporation recognizes gain as if it sold the property to the shareholder at fair market value. That gain flows through on K-1s and increases the AAA like any other income item. The distribution amount equals the property’s fair market value, reduced by any liabilities the shareholder assumes.⁶

If fair market value is less than tax basis, the corporation cannot recognize the loss. The disallowed loss is treated as a non-deductible expense and reduces the AAA. When multiple properties are distributed at once, gains on some and losses on others cannot be netted against each other. Each property is handled independently.⁶

What Happens to the AAA if the S Election Ends

The AAA doesn’t vanish when the S election ends. Section 1371(e) gives the corporation a window called the post-termination transition period (PTTP) to distribute remaining AAA balances as tax-free returns of basis. During the PTTP, cash distributions reduce the shareholder’s stock basis to the extent of remaining AAA, with any excess treated as gain from a sale of stock.⁷

The PTTP generally runs from the day after the last day as an S corporation through the later of one year after that date or the due date (including extensions) for filing the final S corporation return.⁸

Two limitations catch people off guard. Only distributions of money qualify for PTTP treatment; property distributions don’t count. And once the AAA is exhausted during the PTTP, further distributions fall under the regular C corporation rules of Section 301, meaning they’re taxable dividends to the extent of earnings and profits.⁹

When You Actually Want to Distribute AEP First

The default ordering puts the AAA first, which is usually what shareholders want. But sometimes an S corporation actually wants to clear its AEP first. The AAA bypass election under Regulation 1.1368-1(f) lets the corporation skip the AAA and treat distributions as coming from AEP, making them taxable dividends.¹⁰

Why would anyone volunteer for taxable dividends? Because AEP creates two serious problems for an S corporation. Under Section 1375, if the corporation has AEP and more than 25 percent of its gross receipts are passive investment income (rents, royalties, dividends, interest, and annuities), it owes a corporate-level tax on the excess net passive income, calculated at the highest corporate rate.¹¹ Worse, if that same combination persists for three consecutive tax years, the S election terminates automatically, and the corporation cannot re-elect S status for five years without IRS consent.¹²

Distributing enough AEP to zero out the balance eliminates both threats. The bypass election can be paired with a deemed dividend election under Regulation 1.1368-1(f)(3), which treats a specified amount as if it were distributed from AEP even though no cash changes hands. The deemed dividend election requires a statement attached to a timely filed Form 1120-S identifying the amount allocated to each shareholder, with consent from every shareholder, and it is irrevocable for the year in which it’s made.¹⁰

Record-Keeping and Common Mistakes

The corporation must keep a continuous year-by-year record of the AAA balance starting from the date of the S election. This record supports the amounts on Schedule M-2 and should track every adjustment in the correct order: income increases first, then expense decreases, then distributions, then any net negative adjustment.¹

If the corporation cannot produce auditable AAA records, the consequences are predictable. The IRS will treat all distributions as sourced from AEP, taxing them as ordinary dividends, and the burden of proof falls on the corporation to demonstrate its AAA balance and the tax-free character of its distributions.⁵

In practice, AAA record-keeping breaks down in a few recurring ways: failing to separate tax-exempt income into the OAA, applying the ordering rules in the wrong sequence, and neglecting to adjust for non-deductible expenses. The IRS practice unit on S corporation distributions specifically flags the improper inclusion of tax-exempt income in the AAA as a common audit finding.⁵ Corporations that converted from C corporation status years ago sometimes assume the AEP has been used up without actually tracing the distributions, and that assumption tends to surface during examination. Keeping the AAA reconciliation current each year, rather than reconstructing it later, is the simplest way to avoid every one of these problems.

1
Internal Revenue Service. 2025 Instructions for Form 1120-S
2
Office of the Law Revision Counsel. 26 USC 1368 – Distributions
3
GovInfo. 26 CFR 1.1368-2 – Accumulated Adjustments Account
4
Internal Revenue Service. Adjustments to Stock Basis
5
Internal Revenue Service. Distributions with Accumulated Earnings and Profits
6
Internal Revenue Service. S Corporations Property Distribution
7
Office of the Law Revision Counsel. 26 USC 1371 – Coordination with Subchapter C
8
eCFR. 26 CFR 1.1377-2 – Post-Termination Transition Period
9
Federal Register. Eligible Terminated S Corporations
10
eCFR. 26 CFR 1.1368-1 – Distributions by S Corporations
11
Office of the Law Revision Counsel. 26 USC 1375 – Tax Imposed When Passive Investment Income Exceeds 25 Percent of Gross Receipts
12
Office of the Law Revision Counsel. 26 USC 1362 – Election; Revocation; Termination