In Argentina, a similar condiment known as salsa golf, or “golf sauce,” is a popular dressing for fries, burgers, and steak sandwiches. According to tradition, the sauce was invented by Nobel laureate and restaurant patron Luis Federico Leloir at the “Golf Club” in Mar del Plata, Argentina.
In Brazil, many fast food restaurants provide “rosé sauce” (equal parts mayonnaise and ketchup, sometimes with hot sauce added) alongside the traditional ketchup and mustard with fries and onion rings.
In Costa Rica, a salad dressing called Salsa Rosada (pink sauce) is served with a cabbage salad. The main Salsa Rosada ingredients are ketchup and mayonnaise.
In Flanders, Belgium, the mixture of mayonnaise and ketchup is known as “cocktailsaus”, often refined with the addition of some paprika powder or whisky. Mayonnaise and ketchup separately on a dish (usually fries) and topped with freshly chopped onion is known as “speciaal”. A mixture of ketchup, mayonnaise, finely chopped onion and sometimes spices is known as “riche”, literally “rich sauce”.
In the Netherlands a variation of mayonnaise is served with fries which is calles fritessaus, it contains less fat then regular mayonnaise. In contrast to Flanders a frites speciaal consists of French fries, fritessaus, curry ketchup, and finely sliced onions.
In France, many Turkish restaurants and other fast-food establishments serve fry sauce and call it sauce américaine; it is also common for customers to request “ketchup-mayo”—a dab of mayonnaise and a dab of ketchup—alongside their French fries at such places. Both American sauce and the more thousand-island like sauce cocktail (somewhat similar to that of Iceland) can often be found in supermarkets, and occasionally also premixed “ketchup-mayo.”
In Germany, a popular product called ‘Rot Weiss’, meaning ‘red white’ is sold in toothpaste-style tubes, and consists of ketchup and mayonnaise.
In Iceland, a condiment similar to fry sauce called Kokkteilsósa (“cocktail sauce”) is popular. Originally, the sauce was used with prawn cocktails—hence the name—but in course of time, it became indispensable with French fried potatoes. However, Icelanders use the sauce with many other dishes, including hamburgers, pizza, hotdogs, and fried fish. Substituting sour cream for some part of the mayonnaise is also popular, making the resulting sauce thicker and somewhat healthier.
In Ireland the sauce is commonly known as pink sauce, cocktail sauce or burger sauce and is enjoyed as an accompaniment to chicken goujons, chips and burgers.
In Macedonia, liberal amounts of ketchup and mayonnaise are often served with grilled sandwiches, French fries, and the ubiquitous Balkan hamburger-like pleskavica.
In Puerto Rico, the sauce is commonly known “mayoketchup” and is prepared with ketchup, mayonnaise, garlic and a hint of lemon. The sauce is often used as a dip for sorullos and other fried dishes as part of the traditional cuisine of Puerto Rico.
In Québec, Canada, it is one of the standard sauces eaten with fondue chinoise.
In the United Kingdom, fry sauce is commonly known as burger sauce. Mustard is often added.
In Venezuela, fry sauce is known as ‘Salsa Rosada’(same as Costa Rica) and it’s usually served at parties with snacks like Meatballs, Pigs in a blanket and Tequeños.

There you have it, it’s practically universal.