He was born on August 19, 1751 in Concord, Massachussets, United States, the son of Dr. Abel and Abigail (Brigham) Prescott and a descendant of John Prescott who settled in New England in 1640. Both his father and his grandfather, Dr. Jonathan Prescott, were physicians.
Prescott followed in the footsteps of his older brother Benjamin and apprenticed under his father, Abel Prescott, for about seven years.
During the latter part of his apprenticeship or shortly after he began his medical practice in Concord, he became an active member in the patriot movement.
There is evidence that Prescott went on to serve as a surgeon in the Continental Army. The evening of April 18, 1775, he had spent in Lexington, and after one o'clock he started on his journey home by horseback. He overtook Revere and William Dawes, who had just aroused John Hancock and Samuel Adams at the parsonage with the news that the British troops were marching from Boston to destroy the military stores of the provincials at Concord.
Revere found Prescott to be "a high Son of Liberty, " and they all proceeded together on the road to Concord which ran through the northern part of Lincoln. As they approached a pasture on the right (now marked by a tablet), Revere, who was riding ahead, saw two mounted British officers in the moonlight waiting under a tree. Two more officers came through the bars from the pasture and all four spurred up to Revere with pistols in their hands. At sight of the officers Dawes turned rein and escaped down the road. Prescott galloped up to Revere, used the butt end of his whip as a weapon, and they both attempted to push through. But the officers, armed with pistols and swords, forced them into the pasture.
Prescott turned suddenly to the left, he jumped his horse over a stone wall, and made off down a rough farmway into a ravine near a swamp. Revere took to the right in the direction of a wood and was captured there by six other officers. Prescott, being familiar with the country, circled westward until he came out into the fields behind the house of Samuel Hartwell of the Lincoln Minute Men. Here he awakened the household and then sped on to Concord where he gave the alarm.
Prescott was in service at Ticonderoga in 1776. He was taken prisoner on board a privateer afterwards, and carried to Halifax, where he died in jail.
Samuel Prescott is best remembered for his role in Paul Revere's "midnight ride" to warn the townspeople of Concord of the impending British army move to capture guns and gunpowder kept there at the beginning of the American Revolution. Prescott's exploit enabled the Minute Men to assemble and to conceal most of the stores before the British arrived. He was the only participant in the famous ride to reach Concord. A memorial plaque to Prescott is at his former home in Concord, Massachusetts.
He courted Lydia Mulliken, daughter of a well-respected Lexington clockmaker who had died in 1767.
