There has been no confirmation or announcement from V.E. Schwab regarding a fourth book in the Shades of Magic series. However, many fans believe that a fourth book is inevitable, especially given the cliffhanger ending of A Gathering of Shadows. It's possible that Schwab is simply taking her time to write the next installment, or she may be waiting to see how well the third book performs before green-lighting a fourth. Only time will tell for sure whether or not we'll get another helping of this beloved fantasy series.