Sayf al-Din Bilbay or Yalbay (Arabic: الظاهر سيف الدين بلباي; d. 19 September 1468) was a Mamluk sultan of Egypt from 9 October to 4 December 1467.
[3] He was imprisoned by Al-Mansur Fakhr-ad-Din Uthman, then freed by Sayf ad-Din Inal.
During his reign, he became reliant on his dwidar kabir (grand executive), Khairbek.
However, the Dhahiri Mamluks captured Bilbay and deposed him on 5 December 1467, then Timurbugha was proclaimed sultan.
[4] Bilbay was later imprisoned in Alexandria, where he died from plague on 19 September 1468.