Southwest Airlines hiked annual fees on its credit cards, but also announced a host of new benefits and other changes.

Going forward, even more changes are on the horizon. On Thursday, Southwest shared a revamp to its Rapid Rewards Credit Cards. Those adjustments involve new perks that are effective immediately, but come with a cost. Each of the five credit cards will have a spike in annual fees .

For a limited time, now through Sep. 17, new Southwest Rapid Rewards Priority, Premier or Plus consumer credit cardmembers can earn 100,000 bonus points after spending $4,000 in the first five months from account opening. This is double the previous welcome bonus of 50,000 points, and it marks Southwest's best points offer this year.