Term

RASM

Daniel MarkFounder & Editor, Aviatopia
Published Mar 1, 2026Updated Mar 1, 20261 min read

Revenue per Available Seat Mile — an airline metric measuring total revenue generated per seat mile flown, combining ticket and ancillary revenue.

aviation-glossary

Quick Facts

Type
Financial Metric
Also Known As
RASM
Used By
Airlines, Analysts

Definition#

RASM (Revenue per Available Seat Mile) is calculated by dividing total operating revenue by the total available seat miles. It measures an airline's ability to generate revenue from capacity.

Why It Matters Operationally#

When RASM exceeds CASM, the airline is profitable on a unit basis. RASM is influenced by fare levels, load factor, ancillary revenue, and network mix.

See Also

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