Head to head

Atlas V 551 vs Falcon 9

Two vehicles in the same payload class. Every figure below comes from the same two sources for both rockets, and a row appears only when both publish the input.

Payload to low Earth orbit

Relative

Atlas V 551: 18,850 kg

Falcon 9: 22,800 kg

Side by side

11 comparable figures

The highlighted value wins the row. Rows where neither direction is better, like length or stage count, highlight nothing.

Metric	Atlas V 551	Falcon 9
Flights flown	23	697
Success rate	100%	99.4%
Payload to LEO (kg)	18,850	22,800
Payload to GTO (kg)	8,890	8,300
Launch cost	$153M	$52M
Cost per kg to LEO	$8,117	$2,281
Liftoff thrust (kN)	12,269	7,607
Length (m)	59.7	70
Diameter (m)	3.8	3.65
Launch mass (t)	573	549
Stages	2	2

Atlas V 551

Flight record

100% success rate23 of 23 flown

2006peak 2025 · 5 flights2026

Maiden flight 2006-01-19. Retired.

Falcon 9

Flight record

99.4% success rate693 of 697 flown · 4 failed

2010peak 2025 · 165 flights2026

Maiden flight 2018-05-11. Still flying.

Atlas V 551 is built by United Launch Alliance of the United States (company profile on Space Index).Falcon 9 is built by SpaceX of the United States (company profile on Space Index).

Full specifications and the complete launch history for each: Atlas V 551 · Falcon 9.

Specifications from Launch Library 2 by The Space Devs, launch records from Space Index. Derived figures are computed here; see sources and method.