The answer to this question depends on how strict of a vegan you are.
That might sound weird, but it’s pretty clear when we look at the nutritional information and ingredients for fries at Wendy’s.
Wendy’s French Fries Ingredients
There’s quite a few ingredients aside from potatoes in their fries:
Potatoes, Vegetable Oil (Contains One Or More Of The Following Oils: Canola, Soybean, Cottonseed, Sunflower, Corn), Dextrose, Sodium Acid Pyrophosphate (To Maintain Natural Color). Cooked In Vegetable Oil (Soybean Oil, Vegetable Oil [May Contain One Or More Of The Following: Canola, Corn, Or Cottonseed], Hydrogenated Soybean Oil, Dimethylpolysiloxane [Anti-Foaming Agent]. Seasoned With Sea Salt. COOKED IN THE SAME OIL AS MENU ITEMS THAT CONTAIN WHEAT, MILK, AND FISH. Salt: Sea Salt.
The actual fries themselves consist of potatoes and a ton of different vegetable oils, all of which are vegan. Side note: Dimethylpolysiloxane is an ingredient derived from silicon in an industrial process, which is also vegan.
I highlighted the big potential issue, which is that Wendy’s reuses oil from other menu items to cook their fries.
How Big of a Deal is Cross-Contamination?
If you’re vegan because of allergies to milk or fish, you probably don’t want to take the chance of your fries being contaminated.
Likewise, if you’re a very strict vegan, you may not consider them vegan.
But, I think that most vegans would say that the microscopic (if any) amount of dairy or fish here isn’t too big of a deal and that Wendy’s fries are vegan for most vegans.
Most importantly, even if your fries are contaminated with a very small amount of fish let’s say, it’s not like you are in any way increasing the demand for fish. You’re in no way contributing to animal cruelty.