Gov. Mike Beebe says Pulaski, Randolph and White counties have been declared federal disasters and people with storm damage are eligible for individual assistance.
Faulkner County, where most of the 15 who died April 27 in the EF-4 tornado were killed, had earlier been approved for assistance.
Beebe's office says Independence County also sought a federal disaster declaration but did not meet damage thresholds to qualify.
President Barack Obama is scheduled on Wednesday to tour areas with tornado damage.
Individual assistance includes help covering costs of temporary housing, home repairs and replacement and other losses. Help is also available for medical and dental costs, and funeral expenses.