Swordfish
A solitary, wide-ranging billfish found in tropical, temperate, and occasionally cold waters across the Atlantic, Pacific, and Indian Oceans, swordfish are the sole member of the family Xiphiidae — distinct from marlin and sailfish in both anatomy and behavior.
They spend daylight hours in near-freezing depths exceeding 1,500 feet, then rise toward the surface after dark to feed. That vertical range, combined with their size and dogged endurance, makes them one of the most demanding targets in offshore fishing.
Scientific Name: Xiphias gladius
Also known as Broadbill, Broadbill Swordfish
- The long, flat, sword-like bill (rostrum) is the defining feature — broader and flatter than a marlin's, and proportionally longer relative to body size.
- Adults are toothless and scaleless, with a round, muscular body that's blackish-brown on top fading to light brown below.
- The first dorsal fin is tall and crescent-shaped; the second is tiny. Pelvic fins are absent entirely — a quick ID point that separates swordfish from all other billfish.
- Common catches run 250–500 lb; the IGFA all-tackle record stands at 1,182 lb, and fish exceeding 14 feet have been documented.
What to know
Habitat Distribution
- A highly migratory, open-ocean species present in all major ocean basins — absent only from the coldest polar waters.
- Tolerates an unusually wide temperature range (roughly 41–81°F) thanks to a specialized organ that warms the brain and eyes, enabling deep, cold-water hunting that most large pelagics can't manage.
- Operates across an extreme depth range — from the surface down to depths exceeding 9,000 feet, though most feeding activity occurs between the surface and about 2,500 feet.
- Mediterranean populations are considered a separate stock from Atlantic fish and face greater pressure; management and stock health vary significantly by ocean basin.
Specific Spots
- During daylight, swordfish hold at extreme depth — typically 1,200 to 2,500+ feet — near temperature breaks and the seafloor, which is why daytime deep-drop fishing targets those specific depth windows rather than the full water column.
- After dark, they follow the deep scattering layer (DSL) — the dense band of squid, lanternfish, and other prey that migrates upward each night — which is why nighttime surface and mid-column presentations can intercept fish that were unreachable by day.
- Water temperature at depth matters more than surface conditions: daytime deep-drop anglers look for 60–70°F water at the target depth, often using SST charts and bathymetric maps to find the right combination of depth and thermal break.
Swordfish FAQ
Answers from onWater's species guide.
What are the best lures and bait for Swordfish?
Rigged squid is the go-to bait across all swordfish fisheries, whole squid or squid chains produce a strong scent trail and match the primary natural prey. Rig them to swim naturally rather than spin.
What do Swordfish eat?
Squid is the primary prey and the most reliable bait, swordfish actively hunt squid as it migrates up the water column at night, and a rigged squid produces the scent trail and profile that triggers strikes at depth.
Where do Swordfish live?
A highly migratory, open-ocean species present in all major ocean basins, absent only from the coldest polar waters. Tolerates an unusually wide temperature range (roughly 41–81°F) thanks to a specialized organ that warms the brain and eyes, enabling deep, cold-water hunting that most large pelagics can't manage.
See it in the app
Most maps show you water.
onWater shows you Swordfish.
- 01 · Species map filter
Map every Swordfish water
Pick Swordfish and the map zeroes in on the waters they call home. No more guessing which lake holds them.
- 02 · Waterbody species
Tap any water. See what lives there.
Species, behavior and seasonal patterns for every lake, river and pond, before you leave the driveway.
- 03 · Angler Intelligence
Ask how to catch Swordfish
Tactics, gear and timing from onWater's AI fishing guide, tuned to the species and the water you're on.
Stop guessing where Swordfish are.
Open the map, filter by Swordfish, and head to water that holds them. Download onWater and plan your next trip in minutes.
- Species map filter
- Angler Intelligence
- Fishing journal
Explore other species
Trout, bass, salmon, panfish and everything in between. Each guide unpacks the behavior, seasons, and tactics that put fish in the net.
No species information available.
Smarter Fishing Starts in the App.
onWater Fish gives you everything you need to plan smarter, fish better, and own every trip from first cast to last.