Daniel Bennett, 26, will make the unofficial record books with his 208lb skate.
The only reason he won’t make it on the official list is because the massive fish had to be thrown back to sea as it is protected. But Mr Bennett is delighted at his place in fishing history.
Photographs taken of his colossal catch confirms a “probable” size, taking into account wingspan and the length from nose to tail end.
A spokesman for the British record fish committee (BRFC) confirmed it was the largest fish recorded as being caught on its current record list.
Mr Bennett was shore fishing from Kilmalaugh Bay on the Isle of Skye last Thursday when the fish took a hold before a two-hour battle to hook a catch of the day.
The angler, from Whitby, North Yorkshire, said: “The key to catching the fish was having a lot of patience. My back is absolutely killing me now though.
“We’ve never caught anything on that scale before, and we guessed it weighed about 150lb. But it was 208lbs. I can’t believe it.”
The skate, a rare protected fish species that looks similar to a stingray, fell for a bait of half a mackerel fillet.
It measured a whopping 88¼in long by 66¾in wide.
The largest fish caught from British shores before was a 159lb skate, reeled in on the Isle of Lewis in 1994.
Mr Bennett – who works in a fishing supplies shop – said: “West Scotland is known for skate fishing but not Skye. We were the first to catch one there for at least 30 or 40 years.
“There was another chap in our group who caught one and it was about 120lb. We thought we’d never find one any bigger, then we did an hour later.
“I was elated when we finally got it. It was a magical moment. When we measured it from nose to tail end and its wingspan we knew it was a record breaker.
“But we knew we had to put it back, quite rightly. Who knows how big it will grow.”
But despite his record haul Mr Bennett revealed his girlfriend, Philippa, was not overly impressed with his fighing feat.
He said: “She is not really that interested. I think people outside the angling world find it harder to see how much of a feat this is.”
Nick Simmonds, secretary of the BRFC, said: “There is not a larger fish recorded as being caught on our current record list.
“Once we receive pictures from Dan we will pass them on to our scientist who will check the images and hopefully confirm the unofficial record.
“It can’t be confirmed as a record as it was not weighed at the scene.
“It will be seriously considered for the Notable Fish List, which was created for situations like this where the fish cannot be weighed.
“This list is historically important, at least in the angling world.”
The British skate is not unlike the big skate – also know as Raja binoculata – which is the largest species of its family in the waters off North America.
They are found along the Pacific coast from Alaska to Baja California, typically to a depth of 390ft and feed on benthic invertebrates (spineless worms) and small fishes.
This species is one of the most commercially important off California and is sold for food.