The difference comes down to when you get the tax deduction. A repair expense is deductible in the year you pay for it. A capital improvement must be capitalized and depreciated over the recovery period of the asset, which is 27.5 years for residential rental property and 39 years for commercial. A $15,000 expense deducted this year reduces your taxable income by $15,000 now. That same $15,000 capitalized on a residential property gives you roughly $545 per year in depreciation deductions spread over nearly three decades.

The IRS draws the line based on what the work accomplishes. A repair restores property to its ordinary operating condition without adding value or extending its useful life. An improvement betters the property, adapts it to a new or different use, or restores it to like-new condition. Fixing a leaky faucet is a repair. Replacing all the plumbing in the building is an improvement. Patching a section of roof is a repair. Installing an entirely new roof is an improvement.

The tangible property regulations provide the framework for making these determinations. Under these rules, you analyze the building structure and each of its major systems separately. The major systems include HVAC, plumbing, electrical, elevators, escalators, fire protection, security, and gas distribution. An expense that might seem like a repair when you look at the whole building could be an improvement when you look at it at the system level.

The IRS also provides safe harbors that simplify the analysis for certain expenses. The de minimis safe harbor lets you expense items costing $2,500 or less per invoice or per item. The routine maintenance safe harbor covers costs to keep property in efficient operating condition if the work is reasonably expected to be performed more than once during the property’s class life. The small taxpayer safe harbor allows owners of buildings with an unadjusted basis of $1 million or less to expense up to $10,000 or 2% of unadjusted basis in improvements each year.

Getting the classification right matters for your tax planning. If you expense something that should be capitalized, you have taken a deduction you were not entitled to and could face penalties if audited. If you capitalize something that qualifies as a repair, you have delayed a legitimate deduction and paid more in taxes than necessary.

This is why tracking repairs and capital expenditures separately in your books matters from day one. A real estate accounting firm that understands these rules will code expenses correctly as they happen, so when tax time arrives the numbers are already organized and defensible. Trying to sort through a year of transactions after the fact to figure out which were repairs and which were improvements is time consuming and prone to errors.