Repairs, Capital Improvements and Depreciation

There is no rule in the tax code that limits how many cost segregation studies a real estate investor can have performed on a property, or how often they can be performed across a hold period. A cost segregation study is an engineering and accounting analysis, not a tax election and not a filing the IRS tracks or counts. What appears on the tax return is Form 4562 reflecting component-level depreciation classifications; nothing on that form identifies a study as the source of those classifications. Because no count of cost segregation studies exists anywhere in the tax system, the only relevant question at each stage of a hold is whether a new study is worth commissioning for that particular placed-in-service event. That question turns on whether usable allocation data already exists in the contractor invoices, the size of the basis involved, and whether engineering-level precision is likely to produce materially better depreciation outcomes than the documents alone would support.

Form 3115 is an accounting method change form, not a cost segregation form. One specific scenario - applying a cost segregation study retroactively to property whose first return has already been filed - does require a Form 3115, and that scenario comes up often enough that the form gets attached to cost segregation conversations generally. But for a property placed in service in the current year, the depreciation method is established on the originally filed return, and no method change is involved. The same logic applies to a separately placed-in-service addition or expansion in a later year: it has its own placed-in-service date, its own basis, and its own depreciation schedule, so cost segregation applied on that return is an original method election, not a change. A Form 3115 is required when a method already in use needs to be corrected or changed - most commonly to recover missed or incorrect depreciation under IRC 446, with a 481(a) catch-up adjustment bringing the prior years into line. Understanding which fact pattern you are actually in determines whether the form is necessary, optional, or irrelevant.

When a prior accountant never claimed depreciation on a rental property, the IRS treats that as an "impermissible method" of accounting, and Form 3115 (Change in Accounting Method) is the correct tool to catch up all missed deductions in one year as a Section 481(a) adjustment. Taxpayers sometimes wonder whether they can intentionally hold off filing the 3115 until a cost segregation study is done, so both the catch-up and the reclassified components hit the return at the same time. There is no IRS rule that forces you to file the 3115 in the very first year you discover the error - but the automatic change procedure includes a five-year restriction on changing the same accounting method item more than once, which affects the timing calculus in a specific way: sometimes the reason to act sooner is not to bunch up losses, but to avoid burning that five-year window before the cost seg is ready. Readers should confirm current procedural rules and automatic change eligibility under the latest Revenue Procedure governing accounting method changes on the IRS website or with qualified counsel.

When property is used for both personal and business or rental purposes, depreciation must be allocated to the business or rental portion - and the IRS does not forgive the portion you failed to claim. Under the "allowed or allowable" rule in IRC Section 1016(a)(2), your cost basis is reduced by the greater of depreciation actually taken or the amount you were entitled to take, whether you claimed it or not. Skipping depreciation on mixed-use property does not preserve basis - it creates a phantom gain on sale. The mechanics and the recovery options are worth understanding before a disposition forces the issue.