To record amortization, debit Amortization Expense and credit Accumulated Amortization for the period’s calculated amount. That is the whole journal entry, and it is the same two lines every month or every year for the life of the asset. The work sits in the number you post: cost basis minus residual value, divided by useful life, prorated if the period is partial. Everything else in this guide exists to help you get that number right and to flag the places where the books and the tax return part ways.
The Entry, With a Worked Example
Say you’re amortizing a software license at $1,250 per month. The monthly entry looks like this:
- Debit: Amortization Expense — $1,250
- Credit: Accumulated Amortization, Software License — $1,250
The debit hits the income statement and reduces net income. The credit lands on the balance sheet in a contra-asset account that sits directly beneath the intangible asset it relates to. Include the asset name, the period covered, and a short description in the memo line. If your accounting software supports recurring entries, set it up once and let it post automatically. Consistency here spares you the catch-up adjustments that draw auditor questions later.
Calculating the Amount to Post
The formula is cost basis minus residual value, divided by useful life in years (or months, if you post monthly). Buy a copyright for $150,000 with a ten-year useful life and zero residual value, and you record $15,000 per year, or $1,250 per month.
Cost Basis
Basis is everything you spent to acquire the asset and get it ready for use. For a patent, that includes development costs like research, working models, attorney fees, and government filing fees. For a copyright, it includes copyright fees, legal costs, and clerical assistance. When you buy a business that includes multiple intangibles, the purchase agreement typically allocates a portion of the total price to each asset, and both buyer and seller are bound by that allocation for tax purposes.1Internal Revenue Service. Publication 551 – Basis of Assets
Costs incurred after acquisition can also add to basis. Legal fees paid to defend a patent against infringement get capitalized into the patent’s cost rather than expensed immediately, and renewal fees that extend a trademark’s legal protection are treated the same way. Add these to the existing basis and amortize the increased total over the remaining useful life.
Useful Life
Useful life is the number of years the asset will contribute to operations. A legal ceiling sometimes sets the outer limit. A utility patent, for instance, expires 20 years from the filing date of the original application.2Office of the Law Revision Counsel. 35 USC 154 – Contents and Term of Patent; Provisional Rights If economic usefulness will end sooner than the legal term, use the shorter period. A patent on technology that will be obsolete in eight years is amortized over eight years, not twenty.
Under GAAP (ASC 350-30), review the useful life periodically. If circumstances change and the remaining life gets shorter or longer, adjust amortization going forward rather than restating prior years.
Residual Value
Residual value is what the asset will be worth when you’re done with it. For most intangibles, this is zero. There is rarely a functioning resale market for an expired patent or an outdated software license. GAAP requires you to assume zero unless the asset will continue to have value beyond your use and a third party has committed to buy it at a set price.
Method and Partial Periods
ASC 350-30-35-6 says the amortization method should reflect the pattern in which the asset’s economic benefits are consumed, and only fall back to straight-line when that pattern can’t be reliably determined. In practice nearly everyone uses straight-line, because proving an alternative pattern is difficult. The result is a uniform expense each period.
Prorate the first year when you acquire an asset partway through the fiscal year. A patent bought on April 1 with a $12,000 annual expense generates a $9,000 charge for the nine months remaining in the calendar year. The final year picks up the leftover months.
Why the Contra-Account Beats Crediting the Asset Directly
You can credit Accumulated Amortization (a contra-asset) or credit the intangible asset account itself. The contra-account is the better default because it preserves the original cost on the books. You can see at a glance both what you paid and how much you’ve written off. The difference between the two is the asset’s net book value, sometimes called carrying value. Buy a patent for $200,000, accumulate $60,000 in amortization, and the balance sheet shows a net book value of $140,000.
When the Book Entry and the Tax Deduction Diverge
The number you post in your books is not always the number you deduct on your tax return. Internal Revenue Code Section 197 requires certain acquired intangibles to be amortized over exactly 15 years (180 months), regardless of actual economic life. An acquired customer list you expect to use for five years still gets spread across 180 months on the tax return. Covered categories include goodwill, going concern value, customer and supplier relationships, workforce in place, acquired patents and copyrights, franchises, trademarks, and covenants not to compete.3Office of the Law Revision Counsel. 26 USC 197 – Amortization of Goodwill and Certain Other Intangibles Once an asset falls under Section 197, no other method is allowed, and the IRS will not let you write it off faster than the 180-month schedule even if you stop using it early.
Self-Created Assets Are Different
Section 197’s 15-year rule applies primarily to acquired intangibles. Self-created patents, copyrights, formulas, and similar items listed under Section 197(d)(1)(C) fall outside the requirement and follow their own depreciation or amortization rules.3Office of the Law Revision Counsel. 26 USC 197 – Amortization of Goodwill and Certain Other Intangibles Self-created trademarks and trade names, however, remain subject to the 15-year schedule because they are specifically listed in Section 197(d)(1)(F), which is carved out of the self-created exclusion.
The Mid-Month Convention
For Section 197 assets, the 15-year clock starts on the first day of the month of acquisition.4eCFR. 26 CFR 1.197-2 – Amortization of Goodwill and Certain Other Intangibles Buy a customer list on June 18 and June counts as a full month. The first-year deduction covers seven months (June through December). Divide cost by 180, multiply by months in the year. A $6,000 customer list acquired in June produces a first-year deduction of roughly $233 ($6,000 ÷ 180 × 7). You also cannot deduct amortization for the month of disposal.
Book-Tax Timing Differences
A patent amortized over ten years on your income statement but 15 years on your tax return creates a deferred tax asset or liability, depending on which schedule produces the larger deduction in a given year. Your accountant tracks the gap through deferred tax accounts so the financial statements reflect both the current tax bill and the future consequences of the timing difference.
When You Need to Deviate From the Schedule
Amortization assumes a steady decline in value. If a competitor renders your patented technology obsolete, or a regulatory change guts the value of a license, the asset may be worth less than its current book value. GAAP requires you to test intangibles for impairment whenever events suggest a decline, and indefinite-lived intangibles like goodwill are tested at least annually.
An impairment loss is recorded separately from routine amortization. Debit Impairment Loss (an income statement account) and credit the asset directly to bring it down to fair value. Under U.S. GAAP, an impairment write-down cannot be reversed later. After the write-down, future amortization is based on the reduced carrying value over the remaining useful life.
Entries at Disposal or Sale
When you dispose of an amortized intangible, remove both the gross asset and its accumulated amortization from the books, record any cash received, and book a gain or loss for the difference. The prior write-offs then re-enter the picture on the tax side. Under Section 1245, the portion of your gain attributable to prior amortization deductions is recaptured as ordinary income rather than the more favorable capital gains rate.5Office of the Law Revision Counsel. 26 USC 1245 – Gain From Dispositions of Certain Depreciable Property Any gain above the recapture amount is capital gain.
Take a trademark bought for $90,000 with $30,000 of amortization deducted, leaving an adjusted basis of $60,000. Sell it for $100,000 and the total gain is $40,000. The first $30,000 (the amount of prior amortization) is ordinary income. The remaining $10,000 is capital gain. If you sell multiple Section 197 intangibles in the same transaction, the IRS treats them as a single asset for recapture purposes, and losses on individual assets in the group can offset gains on others before recapture applies.5Office of the Law Revision Counsel. 26 USC 1245 – Gain From Dispositions of Certain Depreciable Property
Reporting the Deduction on Form 4562
Amortization deductions for Section 197 intangibles go on Part VI (Line 42) of IRS Form 4562, which you complete for any costs whose amortization period began in the current tax year.6Internal Revenue Service. Instructions for Form 4562 – Depreciation and Amortization For each asset, the form asks for a description of the cost, the date amortization begins (the first day of the month of acquisition), the amortizable amount, the code section (typically Section 197 for acquired intangibles), and the current-year deduction (cost ÷ 180 × months in this year’s amortization period).
If you’re continuing to amortize an asset from a prior year and you aren’t otherwise required to file Form 4562, you can report the deduction directly on the “Other Deductions” line of your business return instead.6Internal Revenue Service. Instructions for Form 4562 – Depreciation and Amortization Most businesses already file Form 4562 for depreciation, so amortization simply rides along on the same form.