At the time of this writing, there's little information about the MCU's Kate Bishop available, and her definitive age is unknown. In fact, there's been very little chatter about the "Hawkeye" show she's set to appear in, except for a handful of set photos that show Hailee Steinfeld wearing her costume (via Polygon). Therefore, the best we can do at this point is speculate using what we do know. That includes taking a look at the actress' real-life age and the ones typically applied to her character on the pages of Marvel's comics.
As of May 2021, Hailee Steinfeld is 24 years old and is set to turn 25 on December 11. It would be easy to just attach that number to Kate Bishop, but determining dates is rarely ever that simple in the MCU. In comparison to the source material, "Young Avengers" Vol. 2 notes that she is only 20, and by the time that story wrapped up, she turned 21. Most other versions have stuck in this neighborhood, meaning that it's reasonable to expect Steinfeld's Bishop to be anywhere from 20 to 25 or so.
Whether she's just entering her 20s or is already halfway through in "Hawkeye," Kate Bishop will surely be a founding member of the Young Avengers when the team inevitably joins the MCU all the same. Should Hailee Steinfeld stick with the role, it's safe to assume we'll see the new Hawkeye empty her quiver on bad guys for years to come.
