Southwest Airlines has put out one of most lucrative deals we've seen from them. In short terms, if you book any one flight before September 24th is over for travel up to November 15th, you can bring a companion on any flights you take between January 6th and February 28th, 2021 (you'll just have to pay $5.60 in taxes and fees).
Southwest Bring a Friend for Free Timeframe: 25. Sep. 2020 - 28. Feb. 2021