Stores which bore the brunt of rampaging mobs during the summer riots face another two years before they resume trading at previous levels.
Those most severely damaged estimate bills for repairs and ruined stock could rack up to as much as £1 million.
And some say overall losses, including lost sales, are still impossible to quantify - five months after the looting.
Duncan Mundell, owner of Party Superstore which was set ablaze when rioters took to the streets of Clapham, south-west London, on August 8, estimated his personal setback would be between £100,000 and £250,000.
"It's been an absolute nightmare," he said.
"With the place burning down, all my staff out of work and the whole place was completely gutted - it's going to take up to two years to rebuild it.
"Right at the start, it was particularly hard because I had 30 staff working there whose wages I had to continue to pay.
"I also set up a charity (Street Kids Rescue) three years ago to look after disabled, orphaned and abandoned children in south east Asia and quite a large part of that funding come from the business.
"When I saw my store burning, I thought, how am I going to get the money to keep 4,000 children fed?"
The fire caused more than £800,000 worth of damage to the fancy dress and party shop.
Mr Mundell, 61, also lost the larger part of a collection of fancy dress costumes worth £600,000 which he had built up over 25 years.
He estimates total costs will be somewhere in the region of £1 million. Owing to being underinsured, he expects to incur significant personal losses.
"Since the fire I have not had a day off, I think I have worked 16 hours a day," the married father of two added.
"That's the only way you can fight your way back up and recover. There's no point being angry. In life things happen and you have to just accept them.
"It took 20 years to build the business up and it was all destroyed pretty much overnight. Although I have managed to keep some of our customers, we know that we have lost a lot of them."
Trevor Reeves, 56, whose burning furniture store came to symbolise the violence of the London disorder, said his losses at the 144-year-old family business were currently between £50,000 and £100,000.
Furniture is now being stocked at the next-door premises, where House of Reeves originally housed the side of his business which sold beds.
"We are not fully back up and running. The store that was burnt down still doesn't exist," he said.
Restoring the building is expected to take up to two years or longer.
Mr Reeves, a married father-of-two who runs the company with his brother, Graham, said the family had been devastated by the "horrific" destruction but had "pulled together" in a bid to trade over Christmas and through January.
"I'm shattered, my father has come out of retirement and is working with us but we're still quite a way off," he said.
But the firm, which withstood two World Wars, has been buoyed up by new customers who travelled hundreds of miles to its Croydon site to buy goods after being moved by images of the beleaguered store in August.
It is understood it could take up to a year to rebuild the Carpetright store, in Tottenham, north London, which burnt down on the first night of rioting which swept English cities.
"It was demolished and completely gutted," a spokesman said. "It is nowhere near up and running again. It will take a long time to rebuild."