Speaking to BBC London before the decision was announced, one trader - who did not want to give his name - said he had been forced to take the compensation offer or "leave with nothing".
The trader, whose family has sold fish at the site for 70 years, added: "For what we’ve been offered to vacate the premises, I can’t go and reinstate myself somewhere else.
"I’ve been told to do my best with what I can do. It’s not great at all."
On the wider impact, he said the closures would have a "massive knock-on effect".
"It means there’s no fish market for London, which would mean the populace of London would have to resort to using local fishmongers which obviously isn’t the end of the world, but where are the fishmongers going to get their fish?
"London will be without a fish supplier, so there does need to be another fish market. When and how that’s going to happen I don’t know."
Another trader said the demise of the market started when a decision was made to rid the fish porters of having to have a licence.
"For the younger guys down here it’s not good because no-one’s ever mentioned about the workers - they’re only ever interested in the companies," he added.
Since then, Brexit and the pandemic have both brought down and led to the market's demise, one trader told BBC London.
"It's getting to the point where everything will be bought in a vac-pack," another trader added.