Experienced centre-back Richard Dunne leaves Villa Park have spent last term out of action with because of hip and groin problems.
Dunne's only appearance came last week when he made a substitute appearance for Ireland in the 4-0 victory over Georgia.
American defender Eric Lichaj made 23 appearances for Lambert's team this season having had spells on loan at Lincoln, Orient and Leeds in previous campaigns.
Veteran goalkeeper Andy Marshall has been part of the Villa squad since 2009 without breaking into the team.
Midfielder Jean Makoun has been on loan for most of his two years at the club, most recently with Rennes, and he is expected to join the French club on a permanent basis.
And attacking midfielder Simon Dawkins returns to Tottenham after his spell in the Midlands.