The Southwest travel fund is now up to $11.2 billion in assets, making it the biggest in the United States.
The fund has more than $1.3 trillion in assets under management, according to the Federal Reserve Bank of Atlanta.
It is also the largest fund in the U.S. The $1,000 annual fee paid by Southwest Airlines travelers has increased to $2.50.
Southwest has also added a $500 bonus to its annual fee.
It has also introduced a new bonus structure, where the fund’s top tier, the $1 million level, will be offered in 2019.
The new bonus will be the first in a series of annual bonuses for those who earn the top tier of the fund, which will rise to $5 million by 2019.
Southwest is also looking to add more tier 1 flights to the fund.
The airline said that it would also increase the amount of money in the fund from the $500 annual fee to $1 per ticket.
The bonus will increase the size of the annual fund by $3.2 million.
Southwest Airlines also plans to increase its perks for its employees, with perks including free meals, free entertainment, a free Southwest Lounge card and a $1 off ticket to the 2018 Las Vegas Summer Olympics.