Delta Air Lines will reportedly launch complimentary Wi-Fi service on all domestic flights in the near future.

According to an internal memo obtained by ThriftyTraveler.com, Delta launched a series of test flights with the new in-flight internet service earlier this week, nearly four years after the airline’s CEO Ed Bastian promised free Wi-Fi on all domestic flights.

The Wi-Fi test offers free connectivity on select flights through the end of 2022, with officials saying it would “soon launch complimentary inflight Wi-Fi service on its domestic mainline routes.”

Delta also plans to expand the free service to international flights by the end of 2024.

“Bringing our vision for the future of travel to life requires putting our technology through rigorous tests, scrutinizing every detail to ensure customers are getting speed and reliability that exceeds their expectations,” Delta managing director Glenn Latta told ThriftyTraveler.

“We will offer complementary Wi-Fi on a select number of flights this summer to test our technology and gain valuable insights that will enable us to offer Wi-Fi on Delta that is as fast and reliable as possible for every customer,” Latta continued.

The carrier did not reveal a target date for the official launch of the complimentary Wi-Fi service, nor did it specify if all high-speed Wi-Fi would be free or if there would be a fee to access the best-quality connection.

Delta is currently only offering the test connectivity on mainline routes, not regional flights operated by airlines like SkyWest or Endeavor Air under the banner of Delta Connection. Other carriers have already launched and started testing free Wi-Fi connectivity, including JetBlue, American, Southwest and Hawaiian.