Born in East Granby, Connecticut, he attended the common schools. After moving with his father to Aurora, Ohio, he settled in Pittsburgh, Pennsylvania in 1803. There he studied law and was admitted to the bar in 1806. He practiced in Pittsburgh and also served for several years as editor of the Tree of Liberty. He also served in the Pennsylvania State Legislature.

In 1822, he was elected to the 17th Congress to fill the vacancy caused by the resignation of Henry Baldwin, and was reelected to the 18th Congress. He was an unsuccessful candidate for reelection in 1824 to the 19th Congress.

He was a member of the Pennsylvania constitutional convention in 1837 and played an important role in the establishment of the United States Whig Party in the 1830s.

Forward was an active supporter of the Harrison-Tyler ticket in the U.S. presidential election, 1840. As a reward, Forward was offered the office of United States Attorney for the Western District of Pennsylvania. He declined that appointment but on March 6, 1841 was appointed by President William Henry Harrison to be First Comptroller of the Treasury. He served in that post until September 13, 1841, when he was appointed 15th U.S. Secretary of the Treasury in John Tyler's Presidential Cabinet.

As Treasury Secretary, the Independent Treasury System of 1840, supported by Levi Woodbury, the 13th Secretary of the Treasury, was repealed and the government's funds were deposited once more with commercial banks. Soon after Forward took office, he was asked by Millard Fillmore, then chairman of the U.S. House Ways and Means Committee, to devise a plan to increase the tariff, in response to the serious decrease in revenue caused by the Panic of 1837. He was also asked to develop plans for a Board of Exchequer to receive and disburse customs revenue, since the Independent Treasury System was no longer in effect. In August 1842 a strongly protective tariff was passed. Since constant friction with the new President marred his entire tenure as Secretary of the Treasury, he left Tyler's cabinet on February 28, 1843.

After leaving his Cabinet post in 1843, Forward resumed the practice of law in Pittsburgh until he was appointed by Chargé d'Affaires to Denmark by President Zachary Taylor. He returned from Denmark in 1851 to serve as president judge of the district court of Allegheny County.

He died in Pittsburgh and is interred in Allegheny Cemetery.

Forward Township in Allegheny County is named for Walter Forward.

This article incorporates facts obtained from the public domain Biographical Directory of the United States Congress.