Improvement Basis Calculator

Capital improvements (Betterment, Adaptation, Restoration — BAR test) add to building basis and depreciate over their 27.5/39 year life from in-service date. Repairs are deducted as expense in year incurred. This calculator combines original basis with improvements to compute the adjusted total basis and resulting annual depreciation.

Original building basis

Improvement 1 (e.g., roof)

Improvement 2 (e.g., HVAC)

Improvement 3 (e.g., kitchen)

Other betterments

Depreciation life (years)

Adjusted total basis

$325,000

Total improvements

$65,000

Annual depreciation

$11,818

How the math works

Capital improvements (BAR test: Betterment, Adaptation, Restoration) add to building basis and depreciate over their own 27.5/39 year life from in-service date. This calculator combines original basis with improvements to compute new annual depreciation.

Repairs (vs improvements) are deducted as expense in year incurred. The repair regulations §1.263(a)-3 provide specific tests — get CPA help on borderline items.

Editorial noteMaintained by EveryCalc - Reviewed June 2026

EveryCalc calculators are designed for fast, practical estimates with transparent inputs and no required account. We use plain formulas, visible assumptions, and related tools so visitors can check the result from more than one angle.

Results are informational only. For financial, tax, legal, medical, construction, or other high-impact decisions, verify the output against primary sources or a qualified professional.

Learn more about our review process on the EveryCalc methodology page.

How this calculator works

What this page estimates

This Improvement Basis Calculator is built to give a quick, browser-based estimate for improvement basis. Capital improvements (Betterment, Adaptation, Restoration — BAR test) add to building basis and depreciate over their 27.5/39 year life from in-service date. Repairs are deducted as expense in year incurred. This calculator combines original basis with improvements to compute the adjusted total basis and resulting annual depreciation. The inputs stay on the page during normal use, and the result should be treated as an estimate for planning, comparison, or education rather than professional advice.

Calculation approach

The calculator applies the standard relationship implied by the inputs, then formats the answer so it can be checked and reused. For finance tools, the most important step is using consistent units, rates, time periods, and assumptions before comparing the result with another calculator or outside quote.

Example workflow

For example, start with a realistic value you already know, change one input at a time, and watch how the answer moves. That makes it easier to tell whether the result is being driven by the main amount, the rate, the time period, or a unit conversion.

Practical checks

Use current, real-world numbers when the result affects money, health, tax, or legal decisions.
Run a low, base, and high case when the inputs are estimates.
Check the related calculators below when the next decision depends on a different assumption.

How to interpret the improvement basis result

Best use

Use the result as a planning number for comparing payments, rates, returns, tax reserves, or cash-flow choices before you request a quote or make a commitment.

Cross-check

Compare the answer with the contract, lender estimate, tax form, brokerage statement, payroll record, or invoice that will control the real-world outcome.

Watch for

Do not rely on a single optimistic rate, return, or fee assumption. Money pages work best when you run low, base, and high cases and keep professional advice separate from the estimate.

This page belongs to the Finance calculator library, so the answer should be read in the context of the decision you are modeling rather than as a universal rule.

Before relying on this improvement basis estimate

Most calculator mistakes come from the inputs, not the arithmetic. Use this short audit before you reuse the answer in a spreadsheet, quote, application, or important conversation.

Confirm source numbers

Match balances, rates, fees, taxes, income, and payment dates against the lender quote, payroll record, tax form, statement, invoice, or contract.

Separate cash flow from total cost

A lower monthly payment can still cost more over time if fees, interest, taxes, or a longer term are hidden in the structure.

Run conservative cases

Test at least one higher-cost or lower-return case before using the output for a purchase, refinance, investment, loan, or tax decision.

Rerun this page when the rate, price, term, fee, tax rule, income, expense, or expected holding period changes.

How to Use

Enter original building basis.
Enter cost of each improvement (roof, HVAC, kitchen, other betterments).
Enter depreciation life (27.5 residential, 39 commercial).
Read adjusted total basis and annual depreciation.

Frequently Asked Questions

BAR test for capitalization?

Betterment (improves condition), Adaptation (new use), Restoration (replaces major component or fixes pre-purchase deferred maintenance) — all capitalized. Routine repairs (paint, leaks, dripping faucets) are expensed.

Bonus depreciation?

Through 2026: 80%/60%/40%/20%/0% phase-down of bonus depreciation on improvements with 20-year-or-less recovery class. Cost segregation studies separate eligible items from 27.5/39-year property.

Improvements during ownership vs at purchase?

Same treatment — capitalize, allocate basis, depreciate from in-service date. At-purchase 'rehab' often easier to track via CPA-prepared depreciation schedule.