The firm agree to the settlement Thursday and to pleading guilty to criminal charges related tot he 2010 disaster.
The figure includes nearly $1.3 billion in criminal fines - the biggest criminal penalty in U.S. history - along with payments to certain government entities.
Associated Press reports also that two BP workers face manslaughter charges.
Up to now, the only person charged in the disaster was a former BP engineer who was arrested in April on obstruction of justice charges. He was accused of deleting text messages about the company's response to the spill, not what happened before the explosion.
The settlement, which is subject to approval by a federal judge, includes payments of nearly $2.4 billion to the National Fish and Wildlife Foundation, $350 million to the National Academy of Sciences and about $500 million to the Securities and Exchange Commission.
London-based BP PLC said in a statement that the settlement would not cover any civil penalties the U.S. government might seek under the Clean Water Act and other laws. Nor does it cover billions of dollars in claims brought by states, businesses and individuals, including fishermen, restaurants and property owners. A federal judge in New Orleans is weighing a separate, proposed $7.8 billion settlement between BP and more than 100,000 businesses and individuals harmed by the spill.
The charges BP will plead guilty to are 11 felony counts of misconduct or neglect of a ship's officers, one felony count of obstruction of Congress and one misdemeanor count each under the Migratory Bird Treaty Act and the Clean Water Act. The workers' deaths were prosecuted under a provision of the Seaman's Manslaughter Act. The obstruction charge is for lying to Congress about how much oil was spewing from the ruptured well.
The Deepwater Horizon rig, 50 miles off the Louisiana coast, sank after the April 20, 2010, explosion that was later blamed on time-saving, cost-cutting decisions made by BP and its drilling partners. The well on the sea floor spewed an estimated 206 million gallons of crude, fouling marshes and beaches, killing wildlife and shutting vast areas of the Gulf to commercial fishing.
The government and plaintiffs' attorneys also sued Transocean Ltd., the rig's owner, and cement contractor Halliburton, but a string of pretrial rulings by a federal judge undermined BP's legal strategy to pin blame on them.
U.S. District Carl Barbier in New Orleans will have the final say over the settlement. He is also the judge who is deciding whether to give final approval to the $7.8 billion settlement involving claims brought by Gulf Coast shrimpers, commercial fishermen, charter captains, property owners, environmental groups, restaurants, hotels and others who claim they suffered economic losses.