Arby's - Fish Sandwiches (the Original and King's Hawaiian Deluxe) are back through at least April; new Crispy Fish Flatbread (details)
Bojangles' - New BojAngler fish sandwich (details)
Boston Market - The Baked Cod meal for $7.99 is back and only available on Fridays. The meal includes two sides and cornbread.
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Captain D's - $4.99 Full Meal Deals through March 27, 2016. A choice of new Home-Style Flounder, Fish, or Butterfly Shrimp meals. Each also comes with two sides and hush puppies.
Carl's Jr. / Hardee's - Red Hook Beer Battered Cod Fish sandwich is back.
Checkers / Rally's - 2 for $2 Crispy Chicken and Crispy Fish sandwich mix-n-match deal
Chick-fil-A - Cod Sandwich offered at select locations (it's an optional menu item that the individual franchisees can elect to serve). The sandwich is available individually for around $3 and in a combo for around $6. You can also get just the fish as part of a plate meal for around $7.
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Culver's - Northwoods Walleye for the season plus Butterfly Shrimp and North Atlantic Cod sandwich and plate dinner on the regular menu.
Del Taco - New Beer Battered Shrimp (details)
El Pollo Loco - New Chili Lime Shrimp dishes (details)
Jack in the Box - The Fish Sandwich is back.
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McDonald's - The Filet-O-Fish is two for $5 at some locations. Other locations have $1.79 Filet-O-Fish Fridays.
Panda Express - They have Honey Walnut Shrimp on the regular menu.
Popeyes - The Butterfly Shrimp Tackle Box for $4.99 is back. They've also brought back the the Seafood Mardi Gras menu, which includes Popcorn Shrimp, Fish & Popcorn Shrimp, and Cajun Fish platters.
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Steak 'n Shake - They're again serving a limited-time Fish Sandwich & Fries as well as a Fish Plate.
Subway - They have tuna on the regular menu.
Wendy's - The North Pacific Cod sandwich is back.
White Castle - New Sriracha Shrimp Nibblers. They've also brought back original Shrimp Nibblers and are also offering Clam Strips, Fish Nibblers, and Fish Sliders.
Wienerschnitzel - Fish and Chips is back.