If protein is the only number on the scoreboard, tilapia and salmon are surprisingly close. Cooked tilapia commonly lands around 25–26 grams of protein per 100 grams, while cooked salmon is often in the low-to-mid 20s. The more meaningful split is fat. Salmon is a fatty fish, so it carries more calories but also much more EPA and DHA, the long-chain omega-3s associated with seafood. Tilapia is much leaner. That makes each useful for a different reason rather than turning the comparison into a simple protein contest.
Protein is close enough that portion size can matter more
USDA FoodData Central entries vary by species and preparation, but the general pattern is stable. Cooked tilapia is roughly 125–130 calories and about 26 grams of protein per 100 grams. Cooked Atlantic salmon is often around 200 calories and roughly 22–25 grams of protein for the same weight. A 5-ounce cooked portion therefore supplies plenty of protein from either fish, with only a modest difference between them.
Those numbers should not be read as universal labels. Farmed and wild salmon differ, moisture loss during cooking changes concentration, and restaurant portions are rarely exactly 100 grams. If your goal is simply a protein-rich dinner, both qualify.
Omega-3s create a much bigger gap
Salmon can deliver well over 1 gram of combined EPA and DHA per 100 grams, depending on species and production method. Tilapia contains these fats too, but typically in much smaller amounts—often around a tenth of a gram per 100 grams in standard composition data. The difference is large enough to change what the fish contributes nutritionally.
That does not make tilapia an unhealthy fish. It means “fish” is not one uniform nutrient category. A lean white fish can be an excellent protein source without providing the same marine omega-3 dose as a fatty fish. If EPA and DHA are a priority, salmon is the stronger choice.
Vitamin D and calories pull the comparison in different directions
Salmon also tends to be a substantially better source of vitamin D, although exact values vary between wild and farmed fish. Tilapia’s strength is energy density: because it carries much less fat, it usually supplies fewer calories for a similar amount of protein.
Calling the lower-calorie fish automatically better would miss why salmon has more calories. Much of the extra energy comes from fat, including the omega-3s that make salmon distinctive. The useful question is whether you want a lean protein or a fish that also makes a significant contribution of marine fats.
Cooking can erase the lean-fish advantage
Breading and deep-frying tilapia can add enough oil and coating that the finished dish is more calorie-dense than simply roasted or grilled salmon. The fairest comparison is therefore cooked fish without large amounts of added fat. Sauces, butter, and side dishes belong to the meal’s nutrition, even though they are not part of the raw fillet.
Mercury does not create a major trade-off between these two in U.S. guidance. FDA and EPA list both salmon and tilapia as “Best Choices” for people who need to pay particular attention to mercury. For most shoppers, the practical rule is straightforward: choose tilapia when you want a very lean protein, and salmon when omega-3s and vitamin D are part of the reason you are eating fish.
Cost and format can matter just as much at the store. Tilapia is often sold as mild frozen fillets, while salmon appears fresh, frozen, canned, and smoked. Smoked salmon can be much higher in sodium than a plain fillet, and breaded tilapia can add substantial starch and fat. Comparing plain fillets keeps the species comparison honest; once processing changes, the package label becomes the better guide.
For meal planning, the difference can be used rather than treated as a problem. A salmon dinner may need less added oil because the fish is naturally richer, while very lean tilapia can pair well with avocado, nuts, or an olive-oil dressing if you want more unsaturated fat. Thinking about the entire plate makes the two fish complementary options instead of nutritional rivals.
Sources
- USDA FoodData Central — Reference food-composition database.
- U.S. Food and Drug Administration — Advice about Eating Fish — Mercury categories and fish-consumption advice.