Abstract: Various embodiments of the invention provide a covering with pocket that provides a secure fit, for example, for a mattress. The covering may comprise a free end that is associated with a head of the mattress and a secured end that is associated with a foot of the mattress. The secured end of the covering having a pocket that includes a lower portion to be positioned under the foot of the mattress, a left side portion to be positioned along the left side of the mattress, and a right side portion to be positioned along the right side of the mattress. The pocket includes an expandable material that spans an opening along the lower portion of the pocket. The expandable material, which includes an elastic member and/or an elastic material, may or may not extend into the left side portion or into the right side portion of the pocket.