Those who still haven’t evacuated from regions affected by approaching Hurricane Irma won’t pay more than $100 to leave with some airlines.

As the tropical storm approaches Puerto Rico, the U.S. Virgin Islands, and Florida, airlines including Delta DAL, -3.29% , JetBlue JBLU, -2.01% American AAL, -3.22% , and Frontier US:FTR are capping costs of flights so that people can evacuate safely.

Delta said this week it’s capping airfares for areas affected by the hurricane. On Friday, their airline said it also added more than 5,000 seats and 24 extra flights from San Juan, Miami, Palm Beach, Fort Lauderdale, and Key West since Wednesday.

This comes after a Twitter user noted the company was increasing tickets from $547.59 to $3,258.50 for a flight out of Miami. A spokesman from Delta said that, contrary to this report, the airline has not raised any fares in response to the hurricane and that the price hike was related to dynamic pricing on the third-party travel site where the customer was booking the flight.

George Hobica, founder of flight booking site Airfarewatchdog.com said the price increases were likely not intentional. “I don’t think airlines would be callous or stupid enough to be consciously jacking up fares,” he said. “If there’s any gouge, it’s just the last minute walk-up airfares that are designed for desperate business fliers.”

“As the storm approached we actually reduced the price level of our highest fares (which are typically seen when customers are booking last-minute travel and inventory is limited) to and from cities in its projected path,” he said.

Hurricane Irma: What You Need To Know

American Airlines is also capping pre-tax fares at $99 for main cabin seats on direct flights out of Florida until Sept. 13, a spokesperson told MarketWatch. IT added additional flights from affected areas including St. Maarten (SXM), St. Kitts (SKB), Providenciales, Turks and Caicos (PLS); and San Juan, and Puerto Rico (SJU).

JetBlue is capping direct flights out of Florida at $99 for direct flights or a maximum of $159 for connecting flights. “We want those trying to leave ahead of the hurricane to focus on their safe evacuation rather than worry about the cost of flights,” JetBlue spokesman Doug McGraw told Reuters. (JetBlue did not respond to request for comment.)

In addition to cheap fares for those in Irma’s path, Frontier Airlines has been offering charitable support for victims of Hurricane Harvey. The company donated $1 of every ticket booked on Wednesday, Sept. 6 to the American Red Cross for hurricane relief efforts.

The airline sent relief supplies to Houston on the first flight back to the area after operations were resumed and, for the next week, it is capping all fares to and from Houston at $99 one way. “We are able to make travel affordable in this time of need,” chief operating officer Jim Nides said in a statement.

Other U.S. airlines are waiving fees for passengers re-booking flights in Caribbean destinations as well as Florida, including Allegiant Air, American Airlines, Delta Air Lines, Frontier Airlines, Southwest Airlines, Spirit Airlines, and United Airlines. Under these changes, passengers can alter their itinerary without paying fees that normal amount to $200 or more per passenger.