Standard tartar sauce is not low FODMAP. Most commercial versions contain onion, garlic powder, or both, which are among the highest FODMAP ingredients you can eat. However, tartar sauce is simple enough to make at home with safe swaps, and the result tastes nearly identical.
Why Store-Bought Tartar Sauce Is Usually High FODMAP
Tartar sauce is built on a short ingredient list: mayonnaise, pickles, onion, lemon juice, and seasonings. The problem is that onion is a core ingredient, not a trace flavoring. A typical recipe calls for three tablespoons of finely diced onion per cup of mayo. That’s enough to cause symptoms even in a two-tablespoon serving of the finished sauce.
Commercial brands add further problems. Heinz tartar sauce contains both pure fructose and onion powder. Masterfoods includes whole onion and garlic powder. These concentrated forms of onion and garlic pack more FODMAPs per gram than their fresh equivalents because the water has been removed. Even brands that don’t list onion or garlic on the front label often sneak them in as “natural flavors” or seasoning blends, so reading the full ingredient list matters.
The mayonnaise base can also be a hidden issue. Plain mayonnaise made from oil, egg yolk, and vinegar is low FODMAP. But some commercial mayonnaises, particularly vegan versions, add garlic, onion, or high FODMAP sweeteners. Monash University notes that commercial mayo “can contain additives and sometimes high FODMAP ingredients,” so checking that label is a separate step.
Pickles Are Less Predictable Than You’d Think
Dill pickles seem like they should be straightforward, but their FODMAP status depends entirely on what’s in the brine. Many pickle brands use garlic, onion, or high fructose corn syrup in their pickling liquid. Even if you’re only adding a spoonful of chopped pickle to your sauce, the brine soaks through the entire cucumber during fermentation. There’s no reliable way to know the FODMAP load without checking every ingredient on the jar.
Capers are a much safer alternative. They’re low FODMAP at one tablespoon per serving and deliver a similar briny, acidic bite. If you’re making tartar sauce at home specifically to keep it FODMAP-friendly, capers are the more predictable choice.
How to Make a Low FODMAP Version
A safe tartar sauce only requires a few ingredient swaps from the traditional recipe. Start with a plain mayonnaise you’ve verified is free of garlic and onion. Use the green tops of scallions (spring onions) instead of regular onion. The green parts are low FODMAP because the fructans concentrate in the white bulb, not the leaves. One to two tablespoons of finely sliced green tops will give you the mild onion flavor tartar sauce needs.
For garlic flavor, use garlic-infused olive oil rather than fresh garlic or garlic powder. FODMAPs are water-soluble, not fat-soluble, so infusing oil with garlic extracts the flavor compounds without pulling the problematic sugars into the oil. Replace a portion of the neutral oil in your mayo with garlic-infused oil, or simply stir a teaspoon into the finished sauce.
The rest of the recipe stays the same:
- Lemon juice: Low FODMAP and safe in typical amounts (one to two tablespoons).
- Capers: Low FODMAP at one tablespoon, chopped to mimic the texture of diced pickles.
- Dried dill: Low FODMAP in seasoning quantities.
- Salt, pepper, cayenne: All FODMAP-free.
Mix one cup of safe mayo with your chopped capers, a tablespoon of lemon juice, a teaspoon of garlic-infused oil, a tablespoon of sliced scallion greens, and dried dill to taste. The whole batch keeps in the fridge for about a week.
No Certified Low FODMAP Brand Exists Yet
As of now, no major brand sells a certified low FODMAP tartar sauce. Companies like Fody Foods have built out an extensive line of certified sauces (marinara, BBQ, teriyaki, salsa), but tartar sauce isn’t among them. That means your safest option is homemade, where you control every ingredient.
If you’d rather buy something ready-made, your best bet is to look for a tartar sauce with an ingredient list short enough to verify yourself. You need a mayo base without garlic or onion, pickles or relish without garlic in the brine, and no onion powder anywhere on the label. These products exist in some specialty stores, but they require careful label reading every time, since manufacturers can change formulations without warning.
Serving Size Still Matters
Even with a fully safe homemade version, portion size plays a role in any low FODMAP eating plan. Tartar sauce is calorie-dense because of the mayo base, so most people naturally eat it in small amounts (one to two tablespoons alongside fish). At that serving size, a properly made version should cause no issues. If you’re still in the elimination phase of the diet, stick closer to one tablespoon per meal to minimize any risk from ingredient variability, then adjust once you know your personal thresholds during the reintroduction phase.