What Were the Navigation Acts?

Boston Harbor at Sunset by Fitz Hugh Lane
Corbis via Getty Images / Getty Images

The Navigation Acts were a series of laws imposed by England’s Parliament in the late 1600s to regulate English ships and restrict trade and commerce with other nations. In the 1760s, Parliament made significant changes to the Navigation Acts in order to increase colonial revenue, thus directly influencing the onset of revolution in the colonies.

Key Takeaways: The Navigation Acts

  • The Navigation Acts were a series of laws passed by the English Parliament to regulate shipping and maritime commerce.
  • The Acts increased colonial revenue by taxing the goods going to and from British colonies.
  • The Navigation Acts (particularly their effect on trade in the colonies) were one of the direct economic causes of the American Revolution.


By the time the Navigation Acts were first enacted in the 17th century, England had a long history of mercantile legislation. In the late 1300s, a law was passed under King Richard II stating that English imports and exports could only be transported in English-owned ships, and no trade or commerce could be undertaken in vessels owned by foreign parties. Two centuries later, Henry VIII declared that all mercantile ships had to be not only English-owned, but also built in England and consisting of a majority English-born crew.

These policies helped expand the British empire when colonialism began to take root, and charters and royal patents were issued that continued the tradition of English control over maritime commerce. In particular, legislation regulating the transport of tobacco—a major commodity from the North American colonies —and the prohibition of French goods laid the foundation for the eventual passage of the Navigation Acts.

Navigation Acts in the 1600s

In the latter part of the seventeenth century, a series of laws called the Navigation Acts were passed, in part due to demand by merchants. These laws allowed Parliament to rigidly define all matters of maritime shipping and trade. Each successive Navigation Act is listed below beneath each act's official title.

An Act for increase of Shipping, and Encouragement of the Navigation of this Nation (1651)

Passed by Parliament under Oliver Cromwell, this law gave the Commonwealth the power to pass further legislation regulating international trade. It also reinforced the previously existing statute that forbade foreign-owned ships from importing or exporting goods to or from England or its colonies. A specific prohibition against the transport of salted fish was aimed at Dutch merchants.

An Act for the Encouraging and Increasing of Shipping and Navigation (1660)

This law further strengthened the Act of 1651. It also tightened restrictions on crew nationality, increasing the required number of English-born sailors from "a majority" to a strict 75%. Captains who failed to ensure this ratio could be forced to forfeit their ship and its contents.

An Act for the Encouragement of Trade (1663)

This law required that any and all cargo bound for the American colonies or other countries had to be routed through England for inspection, and taxes had to be paid upon the goods before they could leave English ports. In effect, this law blocked colonists from forming their own trade economy. In addition,the law led to increased shipping time, which resulted in higher costs on goods.

An Act for the Encouragement of the Greenland and Eastland Trades (1673)

This law increased England’s presence in the whale oil and fishing industries in the Baltic region. It also instituted customs charges on goods traveling from one colony to another.

The Plantation Trade Act (1690)

This law tightened up regulations from previous Acts and gave colonial customs agents the same scope of power as their counterparts in England.

The Molasses Act of 1733

Commerce in the American colonies was tightly restricted by this series of laws restricting trade, but perhaps no Act had as much impact as the Molasses Act of 1733. This law, like the others, was designed to limit trade from the French West Indies. Molasses was a hot commodity, but this act imposed a steep import tax on the product—sixpence on each gallon of molasses—which forced American colonists to buy the more expensive cane sugar from the British West Indies. The Molasses Act was in effect for just thirty years, but those three decades increased English revenue considerably. The year after the Molasses Act expired, Parliament passed the Sugar Act. 

The Sugar Act increased taxes on goods imported into the already financially-strapped colonies, forcing merchants to raise prices. Figures such as Samuel Adams protested against the Sugar Act, believing that its economic impact could be devastating for colonists. Adams wrote:

"[This law] annihilates our Charter Right to govern & tax ourselves – It strikes our British Privileges, which as we have never forfeited them, we hold in common with our Fellow Subjects who are Natives of Britain: If Taxes are laid upon us in any shape without our having a legal Representation where they are laid, are we not reduced from the Character of free Subjects to the miserable State of tributary Slaves?"

Consequences of the Navigation Acts

In England, the Navigation Acts had clear benefits. In addition to creating decades of economic upswing, the Navigation Acts turned English port cities into hubs of commerce thanks to the exclusion of foreign shippers. London, in particular, benefited from the Navigation Acts, and the eventual rapid growth of the Royal Navy helped England become a maritime superpower in the seventeenth century.

In the American colonies, however, the Navigation Acts led to significant upheaval. The colonists felt unrepresented by Parliament, and although most of the Acts had little effect on the average colonist, they drastically affected the livelihoods of merchants. As a result, merchants vocally protested the laws. The Navigation Acts are considered one of the direct causes of the American Revolution.


  • Broeze, Frank J. A. “The New Economic History, the Navigation Acts, and the Continental Tabacco Market, 1770-90.” The Economic History Review, 1 Jan. 1973, www.jstor.org/stable/2593704. 
  • Digital History, www.digitalhistory.uh.edu/disp_textbook.cfm?smtID=3&psid=4102. 
  • “United States History.” Navigation Acts, www.u-s-history.com/pages/h621.html. 
mla apa chicago
Your Citation
Wigington, Patti. "What Were the Navigation Acts?" ThoughtCo, Dec. 6, 2021, thoughtco.com/navigation-acts-4177756. Wigington, Patti. (2021, December 6). What Were the Navigation Acts? Retrieved from https://www.thoughtco.com/navigation-acts-4177756 Wigington, Patti. "What Were the Navigation Acts?" ThoughtCo. https://www.thoughtco.com/navigation-acts-4177756 (accessed May 29, 2023).