What is trailing twelve months (TTM)?

Trailing twelve months (TTM) is the total of a figure, such as revenue or net income, for the most recent 12 consecutive months. It gives a full year of results that moves forward every month, instead of waiting for the fiscal year end.

How it is calculated

Add up the last 12 monthly figures. Each month after that, the newest month comes in and the same month from a year ago drops out:

New TTM = last month's TTM + this month - the same month last year

TTM only works for amounts over a period, such as revenue, expenses or profit. Cash, receivables and other balance sheet items are balances at a date, so use the closing balance or an average instead.

How it is used

TTM smooths out seasonality. A single month can look strong or weak because of timing alone, but twelve months always contain one of each month, so the trend underneath is easier to see. Lenders and buyers often ask for TTM revenue and earnings because they are the most recent full year available.

Worked example

ItemRevenue
TTM to September 2026$1,200,000
Add October 2026+ $110,000
Remove October 2025- $95,000
TTM to October 2026$1,215,000

TTM revenue rose by $15,000, or 1.25%. That is exactly the gap between this October and last October, which is what a TTM change should show.

Common mistakes

  • A missing or doubled month. After a restatement or a late upload, check which months are in the total, not just how many.
  • Comparing TTM with one month. Compare TTM with the prior TTM, and a month with a month.
  • Calling year to date TTM. Year to date restarts every year. TTM never restarts.
  • Summing balances. Twelve month-end cash balances added together mean nothing.

Related terms

  • Month over month (MoM): Month over month (MoM) compares a figure for one month with the same figure for the month before, as a dollar change and a percentage change.
  • Year over year (YoY): Year over year (YoY) compares a figure for a period with the same period one year earlier, such as October 2026 against October 2025.
  • Variance analysis: Variance analysis is the process of comparing actual results with a budget, forecast or prior period, measuring the difference and explaining why it happened.

Further reading