Percy Locke Lancaster was born 26 January 1865, the son of the merchant William Locke Lancaster and his wife Ann Elizabeth (nee LeCronier) Lancaster in Upper Clapton.
Leaving Merchant Taylors in 1881 he joined the family firm of Locke, Lancaster, becoming a director. He was also a director W W & R Johnson & Sons, lead manufacturer.
He was Worshipful Master of the Lodge in 1915.
He died on 25 July 1917, two years after his brother had been killed in the sinking of the Lusitania.