Yardley was founded by William Yardley, who immigrated to America in July, 1682 with his family. He made an agreement with William Penn, before leaving England, to buy 500 acres for ten pounds. A survey was completed in October 1682, and the area William Yardley settled was called "Prospect Farm." It was located just outside of the present Yardley Borough. William Yardley died in 1693, and his family in 1702-1703, possibly of smallpox.
A nephew, Thomas Yardley, came to America in 1704 to settle the estate and never returned to England. He opened a ferry line which started operating in 1710 from Letchworth Avenue, the lower boundary of the village, and landed in New Jersey further downstream. This was an important link between West Jersey and the three roads leading to Philadelphia by way of Falls, Langhorne and Newtown. The Yardley family occupied the land for more than 150 years.
When Yardley was founded there were already small settlements at nearby Burlington, Bristol, and Falls Ferry.
Yardley began to develop into a village about 1807, and by 1880 had a population of 820. Early industries included a spoke and handle factory, sawmill, felloe factory, plate and plaster mill, and two flour mills. The first post office, established in 1828, used the name "Yardleyville." The name became "Yardley" again at the time the Reading Railroad came through the area in 1876.
During the American Civil War, Yardley was a station for the Underground Railroad, an escape route for slaves. Known hiding places were under the eaves of the Continental Hotel (now the Continental Tavern), in bins of warehouses on the Delaware Canal (completed in 1862), and at the General Store (now Worthington Insurance). At Lakeside, the yellow house facing Lake Afton on N. Main St., one brick-walled cellar room is also thought to have been a hiding place.
Yardley Borough was incorporated on March 4, 1895.
The Train Collectors Association, which now boasts worldwide membership of 30,000 individuals, was founded in Yardley in 1954.