The Game-Changing McDonald's Filet-O-Fish Upgrade That Makes It 10x Better

The McDonald's Filet-O-Fish is one sandwich that doesn't have to be complicated to be tasty. With a fried fish patty, tartar sauce, and half a slice of cheese on a steamed bun, it's a simple serving of crunchy seafood goodness. However, innovative fans have discovered that just one change takes the Filet-O-Fish from good to downright delicious: Swapping the tartar sauce for Big Mac sauce.

The tangy, rich, pickle-forward flavor of simple tartar sauce always goes well with fried fish, but Big Mac sauce is essentially tartar's bolder cousin that turns the taste up to 11. It's similarly sweet, tart, savory, and pickle-studded, but with more seasonings to add extra savoriness and depth. Zestier than tartar sauce with the same creamy texture, McDonald's most famous sauce enlivens the mild Filet-O-Fish patty for a sandwich that wows your taste buds.

To try this upgrade, you'll have to order in-person, as the McDonald's app doesn't allow sauce swaps or sauce additions to the Filet-O-Fish (and the same goes for the chain's other sandwiches). Just walk or drive up and ask the staff for a Filet-O-Fish with Big Mac sauce instead of tartar sauce, and they'll likely be willing to accommodate. If you want to make sure the taste comes through, ask for two pumps of sauce on your sandwich, or order a side cup of extra Mac sauce to spread on. There are also more fun ways to try this sauce swap and other tasty mods for your fish sandwich.

A Filet-O-Fish with Big Mac sauce is undoubtedly delectable, but Big Mac fans may miss the substantial heft of their favorite burger. Luckily, multiple customers have reported success when asking for a Big Mac, but with Filet-O-Fish patties instead of beef patties. This allows you to enjoy an extra-tall mashup sandwich with the bonus of lettuce, onions, and pickles. If the staff at your local Golden Arches is confused by your request, try asking for a double Filet-O-Fish, sub Big Mac sauce, and add pickle, lettuce, and onion.

If you're feeling peckish, but not Big Mac-level hungry, simply double or triple the fish on your Filet-O-Fish by asking for a bonus patty or two. In this case, you'll definitely want to request extra Mac sauce for a balanced sandwich. You might also enjoy Filet-O-Fish customizations that give it a diner-style upgrade, plus some extra heft. Ask for added bacon, lettuce, and tomato to enjoy a BLT plus Filet-O-Fish hybrid that's utterly tasty. Even better, you can order these additions in the McDonald's app.

Another fun addition makes McDonald's Filet-O-Fish taste like a British pub staple: fish and chips. Simply order some fries and arrange them on top of the fish patty before adding the top bun, then enjoy. It's a neater, delicious way to enjoy the British classic of breaded fish with crispy fries and tartar sauce.