The direct answer
A T-12 is a trailing 12-month operating statement showing property income and expenses over the most recent twelve months. It complements a rent roll: the rent roll explains who is supposed to pay and under what lease terms, while the T-12 shows what the property actually recorded over time.
Reconcile rental income between the two documents
Compare current scheduled rent from the rent roll with monthly rental income on the T-12. Differences can arise from vacancy, concessions, bad debt, timing, fees or accounting treatment and should be explained.
To apply the approach to an editable scenario, use the NOI Calculator. For the neighboring question, explore Rental Property Calculator.
Normalize nonrecurring and inconsistent items
A T-12 can include one-time repairs, unusual income, owner-specific expenses or seasonal patterns. Underwriting should separate recurring operations from items that are not expected to continue.
Use monthly detail, not only the annual total
Month-by-month trends can reveal rising vacancy, expense spikes or collections deterioration that disappear in a twelve-month aggregate. Pair those trends with lease expirations and current occupancy.
Worked example
If the rent roll shows $60,000 of current monthly scheduled rent but the latest three months of T-12 rental income average only $54,000, the $6,000 gap needs an explanation before the higher run rate is used in a pro forma.
Common mistakes and limitations
Do not annualize one strong current rent-roll month and ignore the operating history. The T-12 and rent roll answer different questions and should be reconciled.
NOI conventions vary in treatment of reserves and owner-specific expenses; debt service and depreciation must not be included as operating expenses.
Frequently asked questions
Is a T-12 the same as a rent roll?
No. A T-12 is a trailing operating statement; a rent roll is a tenant and lease schedule.
Why compare monthly T-12 data instead of just the annual total?
Monthly data can reveal recent changes in vacancy, collections or expenses that an annual total can hide.
Sources and further reading
The article’s examples are illustrative arithmetic. The references below provide context for operating, valuation or transaction concepts; they do not endorse the assumptions or the calculator.
- Office of the Comptroller of the Currency — Comptroller's Handbook — Commercial Real Estate LendingNOI, direct capitalization, cap-rate valuation and DCF concepts for commercial real estate.
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