Southwest Airlines said Friday it is raising the cost of checking a third bag and other fees as it looks to pump up revenues by about $300 million. While Southwest passengers will still be able to check two bags free of charge, the cost of a third one will be bumped up from $50 to $75 in 2013, the Los Angeles Times reported. The airline\'s early boarding fee will rise to $12.50 from $10. It\'s also going to cost people who fail to cancel a restricted ticket before missing a flight, but the carrier hasn\'t said how much that fee will be. \"We are still working through the changes, but we have made the decision to do it,\" Southwest Chief Commercial Officer Bob Jordan said. The Dallas Morning News reported Southwest Chairman Gary Kelly also told an investment conference that in the coming year the airline will begin linking its ticket network with AirTran Airways, which it bought in 2011. \"We have a very solid plan to have AirTran completely integrated into Southwest Airlines by the end of 2014,\" Kelly said.