In this piece · 6 sections
What TTM is, and why buyers use it
Trailing twelve months is exactly what it says: the most recent twelve completed months of revenue and earnings, added up. It rolls forward every month — when June closes, the window becomes July-through-June and the oldest month drops off the back.
That rolling property is the whole point. A calendar year freezes at December 31 and then slowly goes stale — by the following autumn you are still pricing a business on numbers that are nine months old. TTM never lets the window age more than a month.
It also captures a full cycle. Twelve consecutive months include every season exactly once: the peak, the trough, and the ordinary months between. That is why a seasonal site has to be read on TTM — annualizing a strong month overstates the business by multiples, while a full trailing year smooths the curve back to the truth.
So TTM is the compromise that wins: recent enough to reflect the business as it is now, long enough to cancel out seasonality. Recency and completeness, in one number.
TTM vs LTM vs last full year
Three windows get used in valuation conversations, and they are not interchangeable. Knowing which one a buyer means before they say a multiple saves you from comparing two numbers that were never built the same way.
The first thing to clear up: TTM and LTM are the same window — "trailing" and "last" describe the identical rolling twelve months. If a broker says LTM and another says TTM, they mean the same thing. The real divide is between a rolling window (TTM/LTM) and a fixed one (last full year).
Last full year has its place — it lines up with tax returns and any audited statements, so it is the cleanest paper trail. But it ignores everything that has happened since the year closed. A site that doubled in the last six months looks small on last year's books; a site that fell off a cliff looks healthy. TTM catches both.
The trend inside the TTM changes the multiple
Here is the part sellers miss: two sites can post the identical TTM earnings and still command different multiples, because the shape of those twelve months is not the same. A buyer does not just read the total — they read the slope.
The principle underneath both: recency is weighted. The trailing twelve months is the base, but the latest quarter is the strongest evidence of what next year holds. The same logic decides whether profit is read as SDE or EBITDA — the cleaner and more recent the earnings, the more a buyer trusts them.
When brokers annualize the last 3–6 months
For a genuine fast-grower, a strict TTM can understate the business — eight of the twelve months belong to a smaller company that no longer exists. So brokers sometimes annualize the last three or six months instead: take the recent run rate and project it across a year.
It is a legitimate move, but it cuts both ways. Annualizing three months assumes that run rate holds for nine months you have not seen — and it quietly throws away the seasonality protection that made TTM trustworthy in the first place. Annualize a peak quarter and you are back to the exact mistake TTM was built to prevent.
- Defensible when growth is structural, the recent months are not a seasonal peak, and there is a clear reason it continues (a pricing change, a new channel that compounds).
- Risky when the recent run is a launch spike, a viral moment, or the seasonal high — annualizing those manufactures a number that will not repeat.
- The honest compromise: present TTM as the conservative base and the annualized figure as an upside case, clearly labeled — never blend them into one headline number.
How TTM and seasonality interact
TTM and seasonality are two halves of the same discipline. A full trailing twelve months automatically contains one of every season, so the peak and the trough net out — which is precisely why you measure a seasonal business over the whole window instead of any single slice of it.
The trap appears the moment someone reads a partial window on a seasonal site. Annualize the Q4 peak and the business looks enormous; annualize a summer lull and it looks dead. Neither is real. Only the complete trailing year tells the truth — the seasonal revenue guide walks the full mechanics, including why concentration also compresses the multiple.
One subtlety worth holding: even within an honest TTM, where you stand in the cycle colours the trend read. A window that ends right after the peak looks like it is rising; the same business measured right after the trough looks like it is falling. Good diligence normalizes for that before scoring the slope — it does not mistake the calendar position for momentum.
How TTM SDE feeds the band
Once the window is settled, the rest is mechanical. You take the trailing-twelve-months earnings — normalized to SDE or EBITDA after cleaning up the P&L — and apply a multiple. TTM SDE is the base the multiple multiplies. Get the window wrong and every downstream number inherits the error.
The trend then nudges where in the band you land. A clean, rising TTM with a recent strong quarter argues for the upper half; a TTM propped up by stale early months argues for the lower half. That is why a credible estimate returns a range, not a point — the window gives the base, the slope and the risk set the spread.
This is also why RSW's posture is conservative. The band is built on the trailing year you can document, discounted for whatever the recent trend and concentration risks deserve. It should read at or below a broker's quote — none of this is financial advice or a formal appraisal, it is an automated estimate of how the standard earnings window maps to a defensible range.
