Overall very happy with the purchase of this Boden Twin Daybed.  We used a Twin XL Wayfair Sleep 10" Medium Memory Foam Mattress and it fit perfectly.  There would be a small gap if using the regular size as other reviews have mentioned.  Very simple and clear instructions to assemble the bed so there were no issues at all!  This  is a good quality bed that is very versatile since it would go with different styles of furniture and not overpower a small room.  I would highly recommend this bed!!