U.S. · Tax forms
Form 4562 line 42: amortization of costs.
Part VI: which costs you spread over a fixed period, and how column (f) is figured.
Line 42 is for costs whose amortization period begins during your 2025 tax year. Amortization works like straight line: an annual deduction over a fixed period. You describe the costs, the date amortization begins, the amortizable amount and the Code section, and column (f) is the amount divided by the number of months times the months in this year, or the amount times the percentage in column (e). Costs that began in earlier years generally go on line 43, or straight to your return if no other reason to file Form 4562 exists.
Look up a cost type
Result
Costs you can amortize on line 42
| Item | Meaning | Where it goes (per the IRS instructions) |
|---|---|---|
| 167(h) | Geological and geophysical costs | Oil and gas exploration in the United States: ratably over 24 months, starting at the midpoint of the tax year. Major integrated oil companies: 7 years. |
| 169 | Pollution control facilities | Elect to amortize over 60 months (84 months for certain atmospheric facilities placed in service after April 11, 2005). Reduced by any special depreciation allowance. |
| 171 | Bond premium | Elect to amortize taxable bonds acquired after 1987 over the life of the bond. Individuals generally do not report it here; see the Schedule A instructions. |
| 195, 248, 709 | Startup and organizational costs | Business startup costs, corporate organizational costs and partnership organizational costs: a limited amount can be elected as a deduction for the year the business begins, with the rest amortized. |
| 197 | Section 197 intangibles | Goodwill, going concern value, workforce, patents, customer-based and supplier-based intangibles, licenses, covenants not to compete, franchises and trademarks: 15 years (180 months) from the later of acquisition or business start. |
| 59(e) | Optional write-off of preferences | Circulation expenditures 3 years; intangible drilling and development costs 60 months; mining exploration and development costs 10 years. |
| 178, 194 | Lease acquisition and forestation costs | Costs of acquiring a lease (section 178) and qualified forestation and reforestation costs (section 194), subject to the Code section rules. |
The columns
Column (a) describes the costs, (b) is the date amortization begins under the applicable Code section, (c) is the total amortizable amount, (d) is the Code section, (e) is the period or percentage, and (f) is amortization for this year. The instructions say to attach any information the Code and regulations require to make a valid election. Amortized costs do not qualify for the section 179 deduction or for depreciation.
Line 43 and research costs
Amortization that began before your 2025 tax year, other than research or experimental expenditures, goes straight on the Other Deductions or Other Expenses line of your return if you do not need Form 4562 for any other reason. Research or experimental expenditure amortization, including amounts under former section 174(b) and section 59(e) 10-year elections, is reported on line 43 with an attached statement.
Worked example
Kim buys a small business in March 2025 and pays $90,000 for goodwill. Goodwill is a section 197 intangible: 15 years, or 180 months, from March. Monthly amortization is $90,000 divided by 180, or $500. March through December is 10 months in her 2025 tax year, so line 42 column (f) is $5,000 and column (e) can show 180 months.
More IRS form line pages
Other pages in this set: Form 8949 Boxes A-L, Form 5329 Part III, Form 4562 Line 14, Form 4562 Line 12, Form 4562 Convention Codes, Form 5329 Line 52, Form 4562 Line 19, Form 6251 Line 2i, Form 6251 Line 2c, Form 6251 Line 2l. The 1099-R box 7 lookup and W-2 box 12 lookup cover the same kind of question for those forms.
Sources
- Instructions for Form 4562 (2025): the sections for the lines and boxes on this page. Read November 2, 2026.
IRS page last reviewed April 30, 2026. Tax year 2025 edition. Line numbers, dollar limits and dates are those printed in the 2025 instructions and can change. Names in worked examples are made up.
Frequently asked questions
What is line 42 on Form 4562?
Part VI line 42 reports amortization of costs for which the amortization period begins during your 2025 tax year.
How is amortization figured in column (f)?
Divide the column (c) amount by the number of months in the amortization period and multiply by the months included in your tax year, or multiply column (c) by the percentage in column (e).
How long do I amortize goodwill?
Section 197 intangibles such as goodwill are amortized over 15 years (180 months), starting with the later of the acquisition month or the month the business begins.
Where do I report amortization that started in a prior year?
Generally directly on the Other Deductions or Other Expenses line of your return, unless you must file Form 4562 for another reason. Research cost amortization goes on line 43.
Can I take section 179 on amortized costs?
No. The instructions say the part you amortize does not qualify for the section 179 expense deduction or for depreciation.
Not tax advice
This page summarizes IRS instructions, mostly written for the people who prepare the form, and is not tax, legal or financial advice. The payer, a CPA or an enrolled agent can confirm what a box or code means for your return. Everything runs in your browser; nothing you enter is sent anywhere.