The last visitors were admitted into the hall at 2.18am on Friday.
Visitors also made donations worth Bt7 million for the day.
Attendance records were made and repeatedly broken over the past 337 days as people came from all over Thailand to pay their final respects.
Thursday saw the highest turnout of any day, followed by Wednesday (96,150 mourners) and October 1 (90,300 mourners).
In total, 12,739,531 mourners viewed the Royal Urn. Donations received as a form of making merit for the late King have reached Bt889,545,100.01, the Bureau said.
The late monarch’s funeral will be held from October 25-29, with the cremation taking place on October 26.