Cardiff and Manchester Metropolitan University Law Schools and the University of Westminster have all won top marks for their LPCs.
Under the Law Society's new assessment system, inspectors awarded all three of the institutions the 'commendable practice' grade, the highest possible.
Introduced in October, the new system assesses teaching and curriculum standards, assessment procedures, learning resources, student support, leadership, management and quality assurance.
Graham Robson, head of the department for professional legal studies at Westminster, said the course's size gave it an advantage. "We only have 120 full-time students, so we're able to have a close relationship with all of them," he said. "It's easier to deliver a quality product on a smaller course than on a large one. It's easier to have oversight and see what's going on."
Ian Brookfield, director of the centre for professional legal studies at Cardiff, said the school did "a lot of listening to employers" and had a "very helpful local advisory board that helps to steer us".
As reported by Lawyer 2B in February, the College of Law was also awarded the 'commendable' grade.