Constable Keith Palmer was stabbed to death by Khalid Masood on March 22 in the cobbled forecourt of the Palace of Westminster, Parliament’s home.
Two minutes of silence were observed by police throughout the country and by many others to pay respects to the 48-year-old husband and father killed in the line of duty.
Sara Thornton, head of the National Police Chiefs’ Council, said the turnout was impressive.
“We all want to pay honor to the ultimate sacrifice that Keith made,” she said.
Palmer’s coffin lay overnight in a chapel at Parliament after special permission was granted by Queen Elizabeth II.
During the funeral procession, it was covered with a floral tribute that read: “Number 1 Daddy.”
Some 50 members his family, including his wife, child and parents, attended the service at Southwark Cathedral.