The present invention relates to compositions and methods for preserving and extracting nucleic acids from saliva. The compositions include a chelating agent, a denaturing agent, buffers to maintain the pH of the composition within ranges desirable for DNA and/or RNA. The compositions may also include a reducing agent and/or antimicrobial agent. The invention extends to methods of using the compositions of the invention to preserve and isolate nucleic acids from saliva as well as to containers for the compositions of the invention.