S Corp Start-Up Costs: $5,000 Deduction and 180-Month Amortization

An S corporation can deduct up to $5,000 of start-up costs in the tax year it begins business, plus a separate $5,000 of organizational costs, and must amortize anything above those limits in equal monthly installments over 180 months. The S corp start-up costs deduction is automatic: your corporation is treated as having elected it unless you affirmatively choose to capitalize instead. Getting the full benefit depends on sorting expenses into the right category, pinning down the date the business actually started, and combining the immediate write-off with a partial year of amortization in Year 1.

The Two Buckets: Start-Up Costs and Organizational Costs

The tax code treats pre-opening spending as two separate categories, and the $5,000 immediate deduction applies to each one independently. Lumping them together is a common error that can cost you part of the write-off.

Start-up costs are amounts paid while investigating whether to create or buy a business, plus amounts spent after you decide to move forward but before the business begins operating. The test is whether the expense would have been an ordinary deductible business expense if the corporation had already been up and running.¹ Typical examples include market research, travel to scout locations, pre-opening advertising, and wages for employees training before the doors open.

Organizational costs are narrower. They cover expenses tied directly to creating the corporate entity itself: the state filing fee for articles of incorporation, attorney fees for drafting bylaws and charter documents, and accounting fees for setting up the initial books. To qualify, the cost must be connected to forming the corporation, chargeable to a capital account, and of a type that would be amortizable if the corporation had a limited lifespan.²

Costs That Don’t Qualify

Not every pre-opening expense fits into either bucket. Costs of issuing or selling stock are the biggest trap for new S corporations. Fees to print stock certificates, legal costs for stock-purchase agreements, and commissions on selling ownership interests cannot be deducted or amortized. They must be permanently capitalized, typically by reducing the proceeds from the stock transaction.³

Interest, taxes, and research and experimental costs are also carved out of the start-up rules because they have their own deduction provisions elsewhere in the code. You deduct those under their own sections rather than routing them through Section 195.¹

The $5,000 Immediate Deduction and Its Phase-Out

In the year your S corporation begins business, you can deduct up to $5,000 of start-up costs and a separate $5,000 of organizational costs, for a combined potential first-year write-off of $10,000.¹²

Each category has its own phase-out. If your start-up costs exceed $50,000, the $5,000 immediate deduction shrinks dollar-for-dollar by the overage. Once start-up costs hit $55,000, the immediate deduction is gone and everything must be amortized. The same rule applies separately to organizational costs.

Because the phase-outs run independently, high spending in one category does not touch the other. An S corporation with $60,000 in start-up costs and $4,000 in organizational costs gets zero immediate deduction for start-up (fully phased out) but still deducts the full $4,000 of organizational costs in Year 1.

Amortizing the Remaining Balance Over 180 Months

Whatever you cannot deduct immediately is amortized in equal monthly installments over 180 months (15 years), starting with the month your active trade or business begins.¹

Divide the remaining balance by 180 to get the monthly amount. Say your S corporation had $53,000 in start-up costs. The phase-out trims the immediate deduction to $2,000 ($5,000 minus the $3,000 overage above $50,000). The remaining $51,000 amortizes at $283.33 per month.

Don’t Miss the Partial First Year

In the first tax year, you claim both the immediate deduction and a pro-rata share of amortization for the months remaining in that year. This is where new S corp owners often leave money on the table by claiming only the flat $5,000.

Continuing the example: if the business begins October 1, you get three months of amortization (October through December) on top of the $2,000 immediate deduction. Total first-year start-up deduction: $2,000 + ($283.33 × 3) = $2,850. The same math runs separately for organizational costs.

When Your Active Trade or Business Begins

The start date controls everything: which expenses fall under the start-up rules, when amortization begins, and when ordinary current-year deductions kick in.

A business begins when it starts performing the activities it was organized to do. Filing articles of incorporation or getting an EIN does not count. For a retail store, it is the day you open for customers. For a consulting firm, it is when you start serving clients. For a manufacturer, it is when the production line starts running regular output.

Every qualifying expense before that date goes into the start-up or organizational bucket. After that date, ordinary business expenses are fully deductible in the year paid or incurred, with no capitalization requirement. If the IRS disputes your start date and pushes it later, expenses you treated as ordinary deductions can be reclassified as start-up costs subject to amortization, which shrinks the current-year write-off and creates back taxes. Keep evidence such as your first customer invoice, lease commencement date, or first production run record.

How to Elect and Where to Report

The election is automatic. Your S corporation is deemed to have elected to deduct and amortize both start-up and organizational costs unless it affirmatively chooses to capitalize them instead.⁴⁵ No separate election statement is required.

If you instead want to capitalize everything, you must affirmatively elect to do so on a timely filed return, including extensions, for the year the business begins. That election is irrevocable and covers all start-up or organizational costs for the business.⁵

Report amortization in Part VI of Form 4562, Depreciation and Amortization. For each cost category, list a description, the date amortization begins, the total amortizable amount, the applicable code section (Section 195 for start-up, Section 248 for organizational), and the deduction for the year.⁶ The total from Form 4562, including the immediate write-off and the amortization portion, flows to Line 20 of Form 1120-S.⁷

How the Deduction Reaches Shareholders

An S corporation does not pay federal income tax on its own. The start-up and organizational cost deductions reduce the corporation’s ordinary income (or increase its ordinary loss), which passes through to shareholders on Schedule K-1. Each shareholder’s share reduces individual taxable income for the year.⁸

Those same deductions reduce each shareholder’s stock basis. Basis matters because it limits the losses a shareholder can deduct in any given year and affects gain or loss when the stock is sold. Early-stage S corporations often stack start-up amortization on top of operating losses, so keep a running basis calculation to be sure you have enough basis to absorb the deductions flowing through.

If the Business Is Sold or Never Launches

If your S corporation completely disposes of the business before the 180-month period ends, any remaining unamortized start-up costs can be written off as a loss in the year of disposition.¹ You do not lose the tax benefit just because the business did not survive fifteen years.

A different result applies if the business never actually starts. Section 195 only covers costs related to a business that launches, so money spent investigating a venture that is later abandoned does not become a start-up expenditure. For an S corporation, those abandoned investigation costs are generally deductible as a business loss, though the rules are less forgiving for individual taxpayers investigating a first business.

1
Office of the Law Revision Counsel. 26 U.S. Code 195 – Start-up Expenditures
2
Office of the Law Revision Counsel. 26 USC 248 – Organizational Expenditures
3
Internal Revenue Service. AM-2020-003 – Stock Issuance Costs
4
GovInfo. 26 CFR 1.248-1 – Election to Amortize Organizational Expenditures
5
eCFR. 26 CFR 1.195-1 – Election to Amortize Start-up Expenditures
6
Internal Revenue Service. Instructions for Form 4562 (2025)
7
Internal Revenue Service. Instructions for Form 1120-S (2025)
8
Internal Revenue Service. S Corporation Stock and Debt Basis