As “cute” as FIFO & LIFO may sound, they are not the names of stuffed animals. Instead, they are more commonly referred to as “First-In-First-Out” or “Last-In-First-Out” and used for tax lot treatment in stock trading.

By default, all tastyworks accounts are set to FIFO. You may request to change your account’s tax lot from FIFO to LIFO tax lot treatment by contacting us at Changes in tax lot selection methods will only take place going forward and cannot be applied retroactively. 

Furthermore, if you want to make a tax lot treatment change to your account after a trade that was already filled, then you may do so BEFORE the trade settles (stock trades settle T+2 (trade plus 2 days), and options settle T+1). Just contact our trade desk at Please include as much information as possible

Is FIFO or LIFO better? Well, that’s a loaded question, because there are a lot of moving pieces to consider when choosing one tax lot treatment over the other. We advise speaking with a tax professional to determine your best tax lot treatment.