At least 200 people were injured in the April 17 explosion at the West Fertilizer Co. facility in West, Texas, 20 miles north of Waco and 70 miles south of Dallas.
The number of homes destroyed has climbed to 140, Insurance Council of Texas spokesman Mark Hanna said.
"The insured losses should reach $100 million as soon adjusters are allowed to inspect all of the structures and vehicles that were damaged," Hanna said.
"As far as I can tell, every policyholder in West has been contacted by their insurance company and help has been offered," he said.
The council added that the number of those who are uninsured and seeking assistance was high.
President Barack Obama, who will travel to West, Texas, Thursday for a memorial service for the dead and injured, ordered flags at public buildings flown at half-staff for the day.
First lady Michelle Obama planned to attend the service at Baylor University in Waco.
The president was to deliver remarks around 2:15 p.m. CDT, the White House said Wednesday night.
Investigators have not determined the cause of the explosion and the FBI has said it has no indication of criminal activity.
The 7:51 p.m. blast occurred two days before the anniversary of the April 19, 1995, bombing of the Alfred P. Murrah Federal Building in Oklahoma City, an attack set off by explosives made from fertilizer that killed 168 people.
It happened two days after the Boston Marathon twin bombings that killed three people and injured 282 others.
The fertilizer plant in the town of West, population 2,700, exploded as volunteer firefighters and other emergency responders were arriving in response to a fire at the storage and distribution facility.
Most of the 10 first responders killed were found near a 90-foot-wide crater created by a blast so powerful the U.S. Geological Survey registered it as a magnitude-2.1 earthquake.
At least two lawsuits have been filed against West Fertilizer owner-operator Adair Grain Inc.
Adair owner Donald Adair said in a statement Tuesday his company was "working closely" with investigators "and will assist in the fact finding to whatever degree possible."
He said his company would "do everything we can to understand what happened to ensure nothing like this ever happens again in any community." He said he would limit his comments in the coming weeks "out of respect for the investigative process."