People whose homes and businesses were destroyed in rioting could lose out on millions of pounds in compensation if they do not lodge a claim immediately.
Legal experts warn that most insurers require riot damage claims to be made within seven days, or they face getting no money back at all.
Even people who do not have insurance should act quickly.
This is because a 125-year-old Riot Damages Act requires the police to pay out cash to property owners who suffered losses they could not possibly predict.
However, it is only valid if victims give their details to the police within 14 days.
"Any delay is an unnecessary risk," said Stuart White, partner at City law firm Reynolds Porter Chamberlain LLP (RPC).
"Some independent retail units have been completely destroyed by the rioters, making them dependent on recovering the value of the damage to start trading again."
The Association of British Insurers estimates UK businesses and individuals have already racked up losses and damage of over £100m.
With some businesses remaining closed due to damage or the threat of further riots, this figure is rising by the hour.
Richard Hanson-James, of insurance specialists Claim Experts, told Sky News affected firms should do everything possible to get back on their feet, without worrying about preserving evidence for insurers.
"Just make the claim and insurers will send someone down to check it out," he said.
"Don't delay what is essential to your security - such as changing locks and replacing windows.
"Likewise, if you're a restaurant that needs a new freezer in order to operate, for example, go out and get a new one rather than wait to have your claim processed."
Labour leader Ed Miliband has urged the Government to work with the insurance industry to put in place fast-track procedures so that people do not have to wait for payouts to begin making repairs.
"Those who have been the immediate victims of this inexcusable violence cannot be left to cope alone," he said.