Sam is correct on the Confederate casualties per the appendix C in my book The Confederate Alamo. The Confederate casualties at Ft. Whitworth just north of Ft. Gregg were 2 KIA, 2 WIA and 85 captured. The Union official numbers were 122 KIA, 592 WIA but my count per other records brought the Union total to about 811 dead and wounded. The amazing thing about this last stand is that the Ft. Gregg garrison gave Lee's army time to escape from Petersburg under cover of darkness on April 2, 1865. Without the Confederate Ft. Gregg garrison's sacrifice then the ANV would probably have been stuck inside Petersburg with door to door fighting and much destruction and there would not have been any mention of Appomattox in the history books.