Overview
Depreciation mistakes can change taxable income, tax owed, and future depreciation schedules. Common errors include wrong recovery periods, incorrect placed-in-service dates, misclassified property, or using the wrong depreciation method. Correcting them promptly reduces interest, penalties, and surprises at audit.
When do you file an amended return vs. Form 3115?
- File an amended return (for example, Form 1040-X, 1120-X, 1065 amended filings) when the error is limited to a past-year calculation and you need to claim a refund or report additional tax for that year. Amending is the usual fix when the item was simply reported incorrectly on that return.
- File Form 3115, “Application for Change in Accounting Method,” when the correction changes your method of accounting for depreciation (including a §481(a) adjustment that spreads the effect over years). The IRS provides automatic and non-automatic consent procedures for certain depreciation-related method changes (see the Form 3115 instructions).
(See the IRS guidance on Form 3115 and automatic consent procedures: https://www.irs.gov/forms-pubs/about-form-3115)
Step-by-step correction process
- Identify and quantify the error. Reconcile your fixed-asset register, invoices, and depreciation schedules. In my practice, a quick triage is to sort assets by year placed in service and recovery class to spot mismatches.
- Recalculate depreciation for the affected years using the correct cost basis, date placed in service, recovery period, and method (see Publication 946 for rules).
- Determine the remedy:
- If the correction only affects a prior return and you can claim a refund or owe additional tax, prepare an amended return (1040-X, 1120-X, etc.) with a corrected Form 4562 attached if applicable.
- If the correction affects your accounting method for depreciation, prepare Form 3115 to request a change and compute any §481(a) adjustment.
- Prepare supporting documentation: asset invoices, purchase agreements, fixed-asset registers, prior-year Form 4562s, and depreciation schedules.
- File. For amended returns, file within the applicable refund/assessment period (see “Timing and statute of limitations” below). For Form 3115, follow the filing instructions closely — some requests must be filed with the current-year return and others with the IRS centralized office.
(See IRS Publication 946: How To Depreciate Property: https://www.irs.gov/publications/p946 and Form 4562 details: https://finhelp.io/glossary/form-4562-depreciation-and-amortization/)
Timing and statute of limitations
- General refund claims must be filed within three years of the original return date or within two years of the tax payment, whichever is later; substantial understatements can extend assessment periods. For specifics, review the IRS guidance on periods of limitations on assessments and refund claims (IRS Topic No. 152).
- If you expect a refund from correcting an error, file the amended return promptly to preserve your claim.
(IRS period of limitations guidance: https://www.irs.gov/taxtopics/tc152)
Penalties, interest, and audit risk
- If corrected depreciation reduces tax and produces a refund, penalties are unlikely; the issue is usually timing.
- If the correction increases tax owed, expect interest and possibly late-payment penalties. Negligence or substantial understatement can add accuracy-related penalties.
- Proper documentation and timely correction reduce audit risk and support penalty relief requests when appropriate.
Example (concise)
A manufacturer bought machinery for $100,000 and used a 3-year recovery period by mistake instead of the correct 5-year class life. Recalculate the depreciation for the affected years, attach a corrected Form 4562 to an amended return (or file Form 3115 if the correction is treated as a method change), and claim any refund or pay additional tax plus interest.
Documentation checklist
- Original purchase invoices and proof of payment
- Date placed-in-service records (contracts, delivery, installation)
- Fixed-asset register and prior Form 4562s
- Recalculated depreciation schedules showing year-by-year adjustments
- Completed amended returns or Form 3115 and any required statements
Practical tips
- Run periodic depreciation schedule reconciliations at least annually. Accounting software helps but confirm useful life and placed-in-service dates manually.
- Use a qualified tax professional for Form 3115 filings—these can trigger multi-year §481 adjustments and procedural rules.
- If you find many small errors, consider addressing them in a single amended return or a single Form 3115 where permitted.
Helpful FinHelp resources
- Read our guide on filing amendments for detailed filing steps: Amended Returns — Fixing Depreciation Errors
- For line-by-line help with depreciation reporting, see: Form 4562 — Depreciation and Amortization
- If you need a practical walkthrough for business returns, see: Fixing Depreciation Errors on a Previously Filed Business Return
Sources and authority
- IRS Publication 946, “How To Depreciate Property” (current guidance): https://www.irs.gov/publications/p946
- IRS, About Form 3115, “Application for Change in Accounting Method”: https://www.irs.gov/forms-pubs/about-form-3115
- IRS Topic No. 152, “Period of Limitations”: https://www.irs.gov/taxtopics/tc152
Professional disclaimer: This article is educational and not individualized tax advice. For your specific situation, consult a qualified tax advisor or CPA familiar with depreciation and accounting-method changes.

