Southwest will retire approximately 20 Boeing 737-700 aircraft in 2019. The move comes as the carrier begins to take on new 737 MAX 7 aircraft. Southwest currently operates 513 737-700s. [i] Separately, Southwest has agreed to lease 12 737 MAX 8 aircraft from SMBC Aviation Capital, with the first delivery set for this July. [ii]
[i] https://www.ch-aviation.com/portal/news/75057-southwest-airlines-to-retire-20-737-700s-in-2019
[ii] https://www.smbc.aero/news/smbc-aviation-capital-concludes-significant-boeing-737-max-lease-deal-southwest-airlines