Title: Signing of the United States Declaration of Independence
Content:  The Second Continental Congress adopted the Declaration of Independence on July 4, 1776, with 12 of the 13 colonies voting in favor and New York abstaining. The date that the Declaration was signed has long been the subject of debate. Thomas Jefferson, Benjamin Franklin, and John Adams all wrote that it was signed by Congress on the day when it was adopted on July 4, 1776. That assertion is seemingly confirmed by the signed copy of the Declaration, which is dated July 4. Additional support for the July 4 date is provided by the Journals of Congress, the official public record of the Continental Congress. The proceedings for 1776 were first published in 
Title: Independence Day (United States)
Content:  During the American Revolution, the legal separation of the thirteen colonies from Great Britain in 1776 actually occurred on July 2, when the Second Continental Congress voted to approve a resolution of independence that had been proposed in June by Richard Henry Lee of Virginia declaring the United States independent from Great Britain's rule. After voting for independence, Congress turned its attention to the Declaration of Independence, a statement explaining this decision, which had been prepared by a Committee of Five, with Thomas Jefferson as its principal author. Congress debated and revised the wording of the Declaration to remove its vigorous denunciation of the slave trade, 
Title: History of the United States (1776–1789)
Content: The Signers came for the most part from an educated elite, were residents of older settlements, and belonged with a few exceptions to a moderately well-to-do class representing only a fraction of the population. Native or born overseas, they were of British stock and of the Protestant faith. On July 2, 1776, the Second Continental Congress, still meeting in Philadelphia, voted unanimously to declare independence as the "United States of America". Two days later, on July 4, Congress adopted the Declaration of Independence. The drafting of the Declaration was the responsibility of a Committee of Five, which included John Adams, Thomas Jefferson, Roger Sherman, Robert Livingston, and Benjamin Franklin; it 
Title: Signing of the United States Declaration of Independence
Content:  The signing of the United States Declaration of Independence occurred primarily on August 2, 1776, at the Pennsylvania State House, Independence Hall in Philadelphia, Pennsylvania. The 56 delegates to the Second Continental Congress represented the 13 colonies, 12 of which voted to approve the Declaration of Independence on July 4, 1776. The New York delegation abstained because they had not yet received instructions from Albany to vote for independence. The Declaration proclaimed the signatory colonies were now "free and independent States," no longer colonies of the Kingdom of Great Britain and, thus, no longer a part of the British Empire. The signers’ names are grouped by state, with the exception of John Hancock, as President of the Continental Congress; the states are arranged geographically from south to north, with Button Gwinnett from Georgia first, and Matthew Thornton from New Hampshire last. The final draft of the Declaration was approved by the Continental Congress on July 4, although the date of its signing has long been disputed. Most historians have concluded that it was signed on August 2, 1776, nearly a month after its adoption, and not on July 4 as is commonly believed.
Title: United States Declaration of Independence
Content:  several who were not even elected to Congress until after that date. The Declaration was transposed on paper, adopted by the Continental Congress, and signed by John Hancock, President of the Congress, on July 4, 1776, according to the 1911 record of events by the U.S. State Department under Secretary Philander C. Knox. On August 2, 1776, a parchment paper copy of the Declaration was signed by 56 persons. Many of these signers were not present when the original Declaration was adopted on July 4. Signer Matthew Thornton from New Hampshire was seated in the Continental Congress in November; he asked for and received the privilege 
Title: United States Declaration of Independence
Content:  The United States Declaration of Independence is the pronouncement adopted by the Second Continental Congress meeting in Philadelphia, Pennsylvania, on July 4, 1776. Enacted during the American Revolution, the Declaration explains why the Thirteen Colonies at war with the Kingdom of Great Britain regarded themselves as thirteen independent sovereign states, no longer under British rule. With the Declaration, these new states took a collective first step in forming the United States of America. The declaration was signed by 56 of America's Founding Fathers, congressional representatives from New Hampshire, Massachusetts Bay, Rhode Island and Providence Plantations, Connecticut, New York, New Jersey, Pennsylvania, Maryland, Delaware, Virginia, North Carolina, South Carolina, and Georgia. The Lee Resolution for independence was 
Title: United States Declaration of Independence
Content:  Previously, Maryland's delegates had walked out when the Continental Congress adopted Adams's radical May 15 preamble, and had sent to the Annapolis Convention for instructions. On May 20, the Annapolis Convention rejected Adams's preamble, instructing its delegates to remain against independence. But Samuel Chase went to Maryland and, thanks to local resolutions in favor of independence, was able to get the Annapolis Convention to change its mind on June 28. Only the New York delegates were unable to get revised instructions. When Congress had been considering the resolution of independence on June 8, the New York Provincial Congress told the delegates to wait. But on June 30, the Provincial Congress evacuated New York as British forces approached, and would not convene again until July 10. This meant that New York's delegates would not be authorized to declare independence until after Congress had made its decision.
Title: American Revolution
Content:  In April 1776, the North Carolina Provincial Congress issued the Halifax Resolves explicitly authorizing its delegates to vote for independence. By June, nine Provincial Congresses were ready for independence; one by one, the last four fell into line: Pennsylvania, Delaware, Maryland, and New York. Richard Henry Lee was instructed by the Virginia legislature to propose independence, and he did so on June 7, 1776. On June 11, a committee was created by the Second Continental Congress to draft a document explaining the justifications for separation from Britain. After securing enough votes for passage, independence was voted for on July 2. The Declaration of Independence was drafted largely by Thomas Jefferson and presented by the committee; it was unanimously adopted by 
Title: Confederation Period
Content:   The American Revolutionary War broke out against British rule in April 1775 with the Battles of Lexington and Concord. The Second Continental Congress met in May 1775, and established an army funded by Congress and under the leadership of George Washington, a Virginian who had fought in the French and Indian War. On July 4, 1776, as the war continued, Congress adopted the Declaration of Independence. At exactly the same time that Congress declared independence, it also created a committee to craft a constitution for the new nation. Though some in Congress hoped for a strong centralized state, most Americans wanted legislative power to rest primarily with the states and saw the central government as a mere wartime necessity. The resulting 
Title: Second Continental Congress
Content:  the Articles of Confederation. The Declaration announced the states' entry into the international system; the model treaty was designed to establish amity and commerce with other states, and the Articles of Confederation established "a firm league" among the thirteen free and independent states. These three things together constituted an international agreement to set up central institutions for conducting vital domestic and foreign affairs. Congress finally approved the resolution of independence on July 2, 1776. They next turned their attention to a formal explanation of this decision, the United States Declaration of Independence which was approved on July 4 and published soon thereafter.

Question: when did the continental congress vote to adopt the declaration of independence?
Answer: July 2, 1776.