What does T-12 stand for?

T-12 stands for trailing twelve months. It is a report of a property's actual income and expenses for the most recent twelve months, broken out month by month.

What is the difference between a T-12 and a proforma?

A T-12 records what a property actually earned. A proforma projects what it might earn under a buyer's plan. A proforma is not dishonest by itself; the risk is unsupported assumptions layered on top of the actuals. The T-12 is the baseline those assumptions should be checked against.

What is the difference between a T-12 and a T-3?

Both are trailing windows of actual performance. The T-12 covers the last twelve months; the T-3 annualizes the last three. Buyers compare them because the T-3 shows the current run rate: if T-3 income is far above the T-12, rents were pushed recently and the buyer will ask whether those rents will hold.

What is a normal expense ratio on a multifamily T-12?

Operating expense ratios on stabilized multifamily commonly land between 40 and 55 percent of effective gross income, varying by market, age, and whether taxes and insurance are unusually high. A ratio far below that range on a T-12 is a common sign that real costs are missing.

Why do buyers discount an unverified T-12?

Because they cannot tell which numbers are real. An unverified statement carries a risk premium, which a buyer applies as a higher cap rate. Verifying the T-12 removes that premium, and even a quarter point of cap rate is worth six figures on a small deal.

Learn · T-12 fundamentals

What is a T-12 in commercial real estate?

A T-12 (trailing twelve months, also written T12 or called a TTM statement) is a month-by-month record of a commercial property's actual income and expenses over the most recent twelve months. It is the audit trail of real performance. Its bottom line, net operating income, is what a buyer capitalizes into value, which is why RTOM verifies every T-12 before it reaches a listing.

What a T-12 contains

A T-12 walks from the top line to the bottom line. Rental income starts at gross potential rent, then loses vacancy, concessions, and loss to lease, and gains other income like fees, parking, and utility reimbursements. What remains is effective gross income. Operating expenses come off next: property taxes, insurance, utilities, repairs and maintenance, management, payroll, and turnover. Effective gross income minus operating expenses is net operating income (NOI), the number that drives value.

Because it is broken out by month, a T-12 shows seasonality and one-time events that an annual summary hides. A single month of doubled repairs, a gap in a utility line, or a rent that steps up only in the final quarter all tell a buyer something the yearly total cannot.

Where a T-12 comes from

On a professionally managed property, the T-12 is an export from the accounting system: AppFolio, Yardi, RealPage, Buildium, and similar platforms all produce a twelve-month income statement report. On smaller self-managed properties it is often a spreadsheet built from bank statements and receipts, which is exactly where line items go missing. Buyers ask for the T-12 alongside the current rent roll, because the two documents should reconcile: the rent roll shows who pays what today, and the T-12 shows whether that rent actually arrived.

How buyers read a T-12: five checks

Experienced buyers do not read a T-12 top to bottom; they interrogate it. Five checks cover most of what goes wrong. Each one is worked through with real numbers in the step-by-step T-12 analysis workflow:

Reconcile it to the rent roll. In-place rents times economic occupancy should land near the T-12's collected rent. A gap means concessions, bad debt, or units that are not really paying.
Normalize one-time items. An insurance claim payout, a property tax true-up booked in one month, or a single doubled repair bill all distort NOI in either direction. Underwrite the run rate, not the accident.
Compare the T-3 to the T-12. Annualize the last three months. If that run rate sits far above the twelve-month figure, income was pushed recently and the question becomes whether it holds.
Look for what is missing. No management fee, no insurance line, or an expense ratio well under 40 percent of income usually means costs are sitting outside the statement, not that the property is cheap to run.
Question other income growth. Fees, utility reimbursements, and parking income that grow while the unit count stays flat need an explanation a buyer can verify.

Worked example: why NOI is the whole game

Value in commercial real estate is NOI divided by a cap rate. On a small deal, the cap rate a buyer is willing to use moves price more than almost anything else. Here is the same property at two cap rates a quarter point apart.

Effective gross income (T-12)	$360,000
Operating expenses (T-12)	$210,000
Net operating income	$150,000
Value at 6.00% cap	$2,500,000
Value at 5.75% cap	$2,608,700
Difference from a quarter-point cap move	~$108,700

Verified financials are what move a buyer down that quarter point. Unverified numbers carry a risk discount, so a clean, checkable T-12 is worth real money at the closing table.

T-12 versus proforma

A proforma is a forward projection of what a property could earn under a new owner's plan. It is a normal, useful tool. The problem is not the proforma; it is unsupported assumptions stacked on top of it, like a rent bump with no comps or an expense ratio that no real building hits. The T-12 is the baseline every proforma assumption should be measured against. When a listing leads with the proforma and buries the T-12, that is the signal to slow down. For a side-by-side on one property, see T-12 vs proforma.

How RTOM checks a T-12

RTOM was built around this document. When a T-12 is uploaded, it is parsed line by line and run through 15 detectors that flag the patterns buyers usually catch late or not at all: missing months, a trailing-three effective rent that jumps well above the prior nine, expense categories that are implausibly thin or absent, property taxes booked in one lump instead of accrued monthly, negative-NOI months, and other income that grows without an explanation. A listing only earns a verified badge once those checks pass, so the NOI a buyer sees is the NOI the ledger supports.

The thresholds are concrete. The pre-list rent-lift detector, for example, compares average effective rent in the trailing three months against the prior nine. When the recent average runs more than 10 percent above the prior pace, the statement is flagged as critical until the seller documents why: a prior-nine average of $29,000 a month against a recent $32,500 is a 12.1 percent lift, and a buyer will want to know whether that is durable rent growth or concessions burning off right before a listing.

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Frequently asked questions

What does T-12 stand for?: T-12 stands for trailing twelve months. It is a report of a property's actual income and expenses for the most recent twelve months, broken out month by month.
What is the difference between a T-12 and a proforma?: A T-12 records what a property actually earned. A proforma projects what it might earn under a buyer's plan. A proforma is not dishonest by itself; the risk is unsupported assumptions layered on top of the actuals. The T-12 is the baseline those assumptions should be checked against.
What is the difference between a T-12 and a T-3?: Both are trailing windows of actual performance. The T-12 covers the last twelve months; the T-3 annualizes the last three. Buyers compare them because the T-3 shows the current run rate: if T-3 income is far above the T-12, rents were pushed recently and the buyer will ask whether those rents will hold.
What is a normal expense ratio on a multifamily T-12?: Operating expense ratios on stabilized multifamily commonly land between 40 and 55 percent of effective gross income, varying by market, age, and whether taxes and insurance are unusually high. A ratio far below that range on a T-12 is a common sign that real costs are missing.
Why do buyers discount an unverified T-12?: Because they cannot tell which numbers are real. An unverified statement carries a risk premium, which a buyer applies as a higher cap rate. Verifying the T-12 removes that premium, and even a quarter point of cap rate is worth six figures on a small deal.

Reviewed by Scott Henderson, Senior Multifamily Advisor · Updated July 2026

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