Business shorthand for last twelve months, also known as trailing twelve months. Describes a period of time covered by a financial calculation. For example, LTM interest expense means interest expense incurred over the prior twelve months.

LTM periods are often used when measuring a company's financial health. For example, the LTM period may be used to refer to the prior twelve months of a company's performance or the twelve month period before a certain event, such as an acquisition.