Startup costs that exceed your first-year deduction must be amortized over 180 months, or 15 years, on a straight-line basis. The clock starts in the month your business becomes active, and the monthly deduction is the same every month for the full period. The question of how long to amortize startup costs has one answer under Section 195: 180 months, no shorter, no longer, regardless of industry or entity type.1Section 195 of the Internal Revenue Code defines startup costs as amounts you pay or incur before the business begins operating that would have been ordinary deductible expenses if the business were already up and running.
The 180-Month Rule
Whatever portion of your startup costs isn’t absorbed by the first-year deduction gets recovered ratably over 180 months. Ratably means equal monthly amounts. You cannot front-load the deduction into high-income years, bunch it at the end, or accelerate it for any reason. The period is fixed by statute and applies the same way to a solo consulting practice, a restaurant, and a manufacturing company.
The 180 months run from the month your business starts, not from the calendar year. If you open in March, March is month one, and the amortization runs for exactly 180 months from there.
When the Clock Starts
The commencement date is the month your business becomes active, which is often different from the date you registered the entity or received your EIN. A business is active when it has what it needs to serve customers or produce income: staff, equipment, inventory, and a location where applicable. You don’t have to have earned revenue yet. You just have to be ready.
A restaurant is active when the kitchen is equipped and the staff is trained, even if the first customer hasn’t walked in. A consulting firm is active when the consultant is available for engagements, not when the first client signs. Filing the corporate charter or partnership papers by itself does not start the clock.
Pinning down this date matters for two reasons. It fixes the start of your 180-month schedule, and it determines how many months of amortization you can claim on your first return.
The First-Year Deduction and the $50,000 Phase-Out
In the tax year your business begins, you can immediately deduct up to $5,000 of startup costs rather than amortizing them. For a small venture, that write-off may cover everything, leaving nothing on the 180-month schedule.
The allowance shrinks once your total startup spending crosses $50,000. Every dollar above that threshold reduces the $5,000 allowance by one dollar. Spend $52,500 and your immediate deduction drops to $2,500. At $55,000 or more, the first-year deduction disappears entirely and the full amount goes on the 180-month schedule.
These numbers are set by statute and are not adjusted for inflation. The $5,000 and $50,000 figures have remained unchanged since the Small Business Jobs Act of 2010.
Calculating the Monthly Deduction
The formula is straightforward. Take your total qualifying startup costs, subtract the first-year deduction if any, and divide the remainder by 180. That’s your monthly amortization amount.
Suppose you spend $51,000 on startup costs and your business opens on October 1. Your first-year deduction is $4,000: the $5,000 allowance reduced by $1,000 because you exceeded the $50,000 threshold by that amount. That leaves $47,000 to amortize. Dividing $47,000 by 180 gives you about $261 per month. Because the business started in October, you claim three months of amortization ($783) plus the $4,000 first-year deduction on that year’s return, for a total of $4,783 in year one.
In each subsequent full year, you deduct 12 months of amortization, roughly $3,133 in the example. The months you didn’t claim in the first partial year get tacked onto the end of the schedule, so the full amount is recovered over the full 180 months.
Organizational Costs Follow the Same Schedule
If you formed a corporation or partnership, the legal and administrative costs of creating the entity are organizational costs, and they get their own identical bucket: up to $5,000 deductible in year one, the same $50,000 phase-out, and the balance amortized over 180 months. Corporations use Section 248; partnerships use Section 709. Typical examples include legal fees for drafting articles of incorporation or a partnership agreement, state filing fees, and accounting fees for setting up the entity’s books.
One trap for partnerships: fees related to promoting or selling partnership interests, known as syndication costs, are permanently nondeductible. They cannot be amortized under any provision.
Sole proprietors don’t have organizational costs in this sense, because there’s no separate entity to create. They still get the Section 195 startup cost deduction, but there’s no second $5,000 bucket.
What Counts as a Startup Cost
Startup costs fall into two phases. Investigation covers what you spend before committing: market research, product analysis, labor supply studies, scouting locations. Pre-opening activities cover what you spend after deciding to move forward but before the doors open: training employees, advertising ahead of launch, hiring consultants to set up accounting, traveling to meet suppliers.2Revenue Ruling 99-23 draws the line at the point you decide which business to buy, not when you sign a binding agreement.
Several things that look like startup costs are not. The purchase price of a business or its assets is a capital expenditure under Section 263. Equipment and vehicles follow depreciation rules on their own schedules. Interest, taxes, and research-and-development expenses have their own code sections and are not swept into Section 195 even when incurred before opening. Inventory is deducted through cost of goods sold when the product is sold, not amortized.
Reporting the Amortization
You report startup and organizational amortization on Form 4562, Part VI. In the first year, fill out Line 42 with a description of the costs, the date amortization begins, the amortizable amount, and the code section (195 for startup, 248 or 709 for organizational).
For costs paid or incurred after September 8, 2008, no separate election statement is required. The election to amortize is automatic under Treasury Regulation 1.195-1. The IRS assumes you want the deduction unless you affirmatively elect otherwise. To forgo it and capitalize the costs instead, you have to make that choice on a timely filed return, including extensions, for the year the business begins. Either choice is irrevocable and covers all startup costs for that business.
In later years, if you have no other reason to file Form 4562, you can report the ongoing amortization directly on the “Other Deductions” or “Other Expenses” line of your business return.
If the Business Closes Before 180 Months Are Up
You don’t lose the remaining balance if you shut down or sell the business before the 180 months end. Section 195(b)(2) lets you deduct the unamortized startup costs as a loss in the year the business terminates, subject to the Section 165 loss rules. Section 709(b)(2) does the same for partnership organizational expenses when a partnership liquidates early.
Close a business in year four with ten years of amortization still on the books, and that entire remaining balance becomes deductible in the final year. The requirement is a complete disposition or termination, not just a slowdown.