Swordfish and Marlin are two of the most popular game fish that anglers target around the world. While both fish are members of the billfish family, they have distinct differences in their physical characteristics, behavior, and habitat.
Marlin Vs. Swordfish (The Main Differences)

Physical Characteristics of Swordfish and Marlin:
- Marlin have an elongated body with a spear-like bill that is shorter than their body.
- Swordfish have a cylindrical body with a long, flat bill that is longer than their body. They are more round than marlin in their bodies.
- One of the main defining features of a marlin is its tall and sail-like dorsal fin, whereas swordfish have a shorter dorsal fin.
- Marlin have blue-black stripes on top and white or silver on the bottom, while swordfish have a dark blue-black color on top and a lighter color on the bottom.
- Marlin are members of the Istiophoridae family, while swordfish are members of the billfish family.
Marlin and Swordfish Habitat and Behavior
- Marlin are found in warm deep blue waters but usually stay near the surface.
- Swordfish are also found in deep waters and can live at water temperatures between 40 and 80 degrees Fahrenheit. They are relatively dense fish and can dive as deep as 1,800 feet during the day.
- Marlin can swim up to 60 mph and feed on smaller fish and squid, while swordfish primarily feed on squid, octopus, and fish.
Swordfish, Marlin, and Reproduction:
- Marlin and Swordfish both span multiple times a year when their waters are warm
- Swordfish spawn from December to March and April through August (Based on location)
- Various Species of Marlin Spawn all through the year at different times
The Conservation Status of Swordfish and Marlin:
- Some species of marlin, such as the blue marlin and black marlin, are considered vulnerable due to overfishing.
- Swordfish are not currently considered vulnerable but have been overfished in the past.
The Difference In Taste (Marlin vs. Swordfish)
- Swordfish have a meaty texture and a strong flavor.
- Marlin has a strong flavor but is milder than Swordfish, with less fat
- Visit our article “What Tastes Better Marlin Or Swordfish?” for more information on eating these two fish
Conclusion
Whether you’re an angler or just interested in these incredible game fish, understanding the differences between swordfish and marlin can be highly informative. By learning about their unique traits, behaviors, and habitats, you can gain a deeper appreciation for these remarkable creatures and the crucial roles they play in the marine environment.
No, Swordfish do not have teeth in their mouth.
No, from everything we currently know, a Swordfish Sword does not grow back if it is broken off
The Average Marlin (Females are much bigger than Males) weighs between 200 and 400 pounds.