The best replacement for haddock is halibut.

The best alternatives to haddock are rated as following:
★★★★★  halibut
★★★★★  cod
★★★  pollock
★★★  tilapia
★★  flounder
★  scrod
★  cod for fish and chips
★  hake
★  cod healthier
★  haddock
★  cod better
★  rainbow trout
★  plaice
  perch
  cod fish
  whiting
  cod fish and chips
  orange roughy

Your alternative for haddock is not listed? Suggest!
Speaking about haddock, one probably shouldn't forget about dill.

Other search terms related to haddock and their ratings are:
★★★★★ dill
You have in mind a companion for haddock and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of haddock in all years. Click on graph for more.
haddock
halibut
cod