Tuna Vs Swordfish | Let’s Compare Them

My first time deep sea fishing I caught an impressive 30-pound redfish, after that, I was ‘hooked. You can imagine what catching a huge tuna or swordfish could do to one’s ego!

Tuna vs Swordfish: An In-Depth Comparison

Tuna and swordfish are both large, predatory fish that are popular choices for seafood lovers. But how exactly do these two omega-3-rich fish compare when looking at nutritional profile, taste, mercury levels, cost, availability, and more? This in-depth article will examine the key similarities and differences between tuna vs swordfish.

Nutritional Profile

Both tuna and swordfish are high in protein and low in saturated fat, but there are some key differences in their nutrition facts:

Nutrient (per 3oz serving)TunaSwordfish
Total Fat1g4g
Saturated Fat0.4g1g
Omega-3 Fatty Acids0.2g0.5g
Vitamin B122.2mcg5.4mcg

As you can see, tuna is significantly lower in calories, total fat, and saturated fat compared to swordfish. Tuna also contains less omega-3 fatty acids. However, swordfish contains more selenium, potassium, and vitamin B12.

A tuna fish.
Example of a Tuna fish.

Mercury Levels

Both tuna and swordfish contain mercury, which can accumulate to potentially dangerous levels when these fish are eaten frequently over long periods. Here are the average mercury levels found in each:

FishMercury (ppm)

On average, swordfish contains over 3 times as much mercury as tuna. Because of its high mercury content, the FDA and EPA recommend that pregnant women, women who may become pregnant, nursing mothers, and young children only eat swordfish once per month. For the general population, the recommendations are to eat no more than 3 servings of swordfish per month.

Popularity and Availability

Tuna is by far the most popular seafood in the United States. Americans eat over 3 pounds of tuna per capita each year. It’s versatile nature, affordability, and wide availability make tuna a staple protein source for many people. Nearly all grocery stores regularly carry fresh and frozen tuna steaks, along with a wide selection of canned tuna.

On the other hand, swordfish consumption averages around 0.5 pounds per person annually in the U.S. Due to its high price tag and strong flavor, it is not as widely consumed or available as tuna. Fresh swordfish can be found in some grocery stores, usually at high-end retailers or seafood markets. It is not often kept frozen. Swordfish is more commonly found on restaurant menus than tuna due to its reputation as an indulgent, steak-like fish.

Tuna Vs Swordfish Taste and Texture

Tuna and swordfish each have their own distinct taste and texture profiles:

Tuna – Tuna has a mild, slightly sweet, and meaty flavor. The flesh is firm with large, meaty flakes when cooked. Raw tuna has a smooth, butter-like mouthfeel. This mild taste and versatile texture make tuna an easy addition to salads, sandwiches, pasta, and more.

Swordfish – Swordfish has a bolder, fishier taste compared to tuna’s subtle flavor. The dense, steak-like flesh becomes juicy when cooked. Raw swordfish should not be consumed due to risk of parasites. The hearty texture makes swordfish ideal for grilling, broiling, and frying.

Which fish tastes better comes down to personal preference. Those who enjoy rich, fatty fish may prefer swordfish while mild tuna is more friendly for picky eaters.


There is a significant price difference between tuna and swordfish. Here are average cost comparisons:


  • Canned tuna: $1 – $3 per can
  • Fresh tuna steaks or fillets: $10 – $15 per pound


  • Fresh swordfish steaks: $15 – $25+ per pound

If you see swordfish on a restaurant menu, expect to pay $25 or more for a single swordfish entree.

For shoppers on a budget, tuna clearly provides a more affordable source of protein and omega-3 fatty acids compared to the notoriously pricey swordfish. Canned tuna is one of the least expensive sources of fish protein.

a swordfish in water
Example of a Swordfish.


One area where tuna really shines over swordfish is in its versatility as an ingredient:


  • Excellent raw for sushi and sashimi
  • Works well grilled, baked, or pan-seared
  • Adds protein to salads, sandwiches, wraps, pitas
  • Mixes into pasta, rice bowls, casseroles
  • Great for poke bowls
  • Makes flavorful tuna melts
  • Easy high-protein snack right out of the can


  • Primarily prepared grilled, broiled, or fried
  • Too dense and fishy for many raw applications
  • More difficult to complement other ingredients

Overall, mild-tasting tuna offers far more versatility in cooking and as part of other dishes.

Tuna and Swordfish Sustainability

Both tuna and swordfish had issues with overfishing in the past, but current populations and fishing practices provide hope for sustainability:

  • Many tuna species like bluefin remain critically endangered. But skipjack and albacore tuna fisheries are now well-managed with healthy populations.
  • After being overfished for decades, North Atlantic swordfish have rebounded enough that they are certified sustainable seafood by the Marine Stewardship Council (MSC).

Both fish can be good sustainable options if sourced carefully according to reputable organizations like the MSC. Choosing pole and line-caught tuna and U.S. or Canadian swordfish helps support responsible fisheries.

Want to learn more about fish? Check out Steelhead Trout Vs Salmon

Nutritional Comparison to Other Fish

Here is a nutritional overview of how both tuna and swordfish stack up to some other popular types of fish:

Fish (3oz serving)CaloriesFatProteinOmega-3s
Mahi Mahi1081g22g0.3g

As shown, tuna and swordfish have similar protein as the other fish but tuna is lower in calories, fat, and omega-3s compared to most other options. Swordfish contains more healthy fats than tuna.

The Verdict: Tuna vs Swordfish

So which fish reigns supreme in the battle of tuna vs swordfish? Here are some key takeaways:

  • Tuna is leaner and lower in mercury but swordfish contains more healthy omega-3 fats.
  • Swordfish has a rich, meaty taste but tuna is milder and adapts well to many dishes.
  • Fresh swordfish is pricier but canned tuna is affordable.
  • Tuna offers great versatility while swordfish shines when grilled or broiled.
  • Both can be sustainable seafood choices if properly sourced.

There is no clear winner – tuna and swordfish each have their merits. For budget-friendly tuna sandwiches, salads, and pasta dishes, mild canned or fresh tuna is the way to go. But if you want to indulge in a steak-like seafood dinner, swordfish takes the crown.

The omega-3s in both make them healthy additions to your diet as long as intake guidelines are kept in mind. Choose tuna or swordfish based on your taste, budget, and nutritional needs.

I happen to love tuna. What’s your favorite way to prepare tuna? Tell us about in the comments below.