The Atlantic slave trade connected African embarkation ports with destinations across the Americas for more than three centuries. The estimates below describe its scale, changing chronology, geographic concentration, national organization, and the human losses of the Atlantic crossing. Figures are estimates, and the stated periods and measurement definitions matter: some totals count captives embarking from Africa, while others count people arriving or disembarking.
Contents
- Overall scale and chronology
- African embarkation regions
- Change across 50-year periods
- National carriers
- Destinations and port concentration
- The Middle Passage
Overall scale and chronology
The first probable direct Africa-to-Americas slave voyage dates to 1519. The last trans-Atlantic slave expedition completed its voyage to Cuba in 1867, probably sailing from the Congo River. That places the documented span at more than 300 years, from the first probable voyage in 1519 through the final completed expedition in 1867. (A Brief Overview of the Trans-Atlantic Slave Trade)
For the longer 1501–1866 estimates period, the estimates table records 12,521,354 captives embarking from Africa. The methodology page uses a closely related estimate of 12,520,000 captives departing Africa for the Americas. It estimates that 10.7 million enslaved Africans disembarked, mainly in the Americas. These are not identical measures: the first two figures count departures, while the latter counts people reaching disembarkation. (Trans-Atlantic Slave Trade - Estimates; The Trans-Atlantic Slave Trade Database)
The methodology calculation estimates 41,190 voyages carrying captives from Africa, using 304 embarked captives per voyage. A separate calculation estimates 40,380 voyages arriving with captives, using 265 disembarked people per voyage. The difference reflects the distinction between people who embarked and those who survived to arrival or disembarkation. (The Trans-Atlantic Slave Trade Database)
The trade remained active late in the period covered by these estimates. Between 1821 and 1830, more than 80,000 people per year left Africa in slave ships. The final expedition’s completion in 1867 therefore marks the endpoint of a long chronology, not a trade that was evenly distributed across every year. (A Brief Overview of the Trans-Atlantic Slave Trade)
African embarkation regions
The estimates for 1501–1866 show a highly concentrated pattern of embarkation. West Central Africa and St. Helena supplied 5,694,581 embarked captives, the largest regional total in the table. The Bight of Benin supplied 1,999,069, while the Bight of Biafra supplied 1,594,543. The Gold Coast accounted for 1,209,340 embarked captives.
Other regional estimates were smaller but still substantial. Senegambia and the offshore Atlantic supplied 755,509 embarked captives; Southeast Africa and the Indian Ocean islands supplied 542,673; Sierra Leone supplied 388,776; and the Windward Coast supplied 336,863. These figures cover the full 1501–1866 estimates period and should not be read as measurements for a single year or a single phase of the trade. (Trans-Atlantic Slave Trade - Estimates)
The regional pattern also shifted over time. West Central Africa supplied 1,919,906 embarked captives during 1801–1850. In earlier or different periods, the Bight of Benin supplied 734,863 during 1701–1750, while the Bight of Biafra supplied 655,714 during 1751–1800. Southeast Africa and the Indian Ocean islands supplied 409,854 during 1801–1850. These period-specific figures show why an overall regional ranking does not replace chronology: the importance of particular regions changed during the trade’s several centuries. (Trans-Atlantic Slave Trade - Estimates)
Change across 50-year periods
The estimates record a steep rise from the sixteenth century into the eighteenth century, followed by a lower total in the final partial period. The figures below count embarked captives, not survivors at arrival.
| Period | Estimated embarked captives |
|---|---|
| 1501–1550 | 64,137 |
| 1551–1600 | 213,363 |
| 1601–1650 | 667,902 |
| 1651–1700 | 1,207,745 |
| 1701–1750 | 2,560,629 |
| 1751–1800 | 3,933,989 |
| 1801–1850 | 3,647,979 |
| 1851–1866 | 225,610 |
The lowest listed total is 64,137 for 1501–1550. It rose to 213,363 in 1551–1600 and 667,902 in 1601–1650. The next half-century recorded 1,207,745 embarked captives, followed by 2,560,629 in 1701–1750. The highest listed 50-year total was 3,933,989 during 1751–1800. The 1801–1850 figure was 3,647,979, while the shorter 1851–1866 period recorded 225,610. Because the final period covers only 16 years, it is not directly comparable with the preceding 50-year periods as a full-period total. (Trans-Atlantic Slave Trade - Estimates)
National carriers
The national-carrier estimates identify Portugal/Brazil as the largest listed carrier grouping, with 5,848,266 embarked captives during 1501–1866. Great Britain is listed with 3,259,441, France with 1,381,404, and Spain/Uruguay with 1,061,524. The Netherlands is listed with 554,336, the United States with 305,326, and Denmark/Baltic with 111,040. These labels and totals describe the categories used in the estimates table for the full period; they do not turn the figures into a simple count of modern national responsibility. (Trans-Atlantic Slave Trade - Estimates)
Selected periods illustrate how the carrier pattern varied. Portugal/Brazil carried 1,299,969 embarked captives during 1826–1850. Spain/Uruguay carried 400,728 in that same period. Great Britain carried 832,047 during 1751–1775, while the Netherlands carried 132,330. France carried 433,061 during 1776–1800, and Denmark/Baltic carried 39,199 during that period. The United States carried 109,545 during 1801–1825. (Trans-Atlantic Slave Trade - Estimates)
Destinations and port concentration
The geography of arrival was concentrated in the Caribbean and South America. Those regions received 95% of enslaved people arriving in the Americas during 1501–1866. Less than 4% disembarked in North America, and just over 10,000 captives disembarked in Europe. A separate overview estimates that about 40% of the trans-Atlantic slave trade eventually went to Brazil, for the approximate period 1560–1867. It also states that the United States absorbed 5% of Africans arriving in the Americas during 1501–1867. (Introductory Maps to the Transatlantic Slave Trade; A Brief Overview of the Trans-Atlantic Slave Trade)
The destination pattern was also linked to plantation production. A comparative map covering 1501–1900 states that 80% of captives carried from Africa were taken to sugar-growing areas. The seven largest organizing ports—Rio de Janeiro, Bahia, Liverpool, London, Nantes, Bristol, and Pernambuco—carried almost three-quarters of captives removed from Africa. The port statistic refers to organizing ports and an approximate 1500–1867 period, while the sugar statistic uses a comparative map period through 1900; they should not be treated as measurements from one identical table. (Introductory Maps to the Transatlantic Slave Trade)
African departure ports could be extremely important individually. Luanda alone dispatched about 1.3 million enslaved people from the 1570s into the nineteenth century. Luanda, Whydah, and Bonny together accounted for about 2.2 million slave departures during the approximate period from the 1570s to the nineteenth century. Bonny sent four-fifths of all the captives it exported during 1760–1840. (A Brief Overview of the Trans-Atlantic Slave Trade)
The Middle Passage
The voyage itself imposed severe conditions and losses. Children made up no less than 26% of people on board in the overview’s estimate of the trade. Slave traders typically packed two captives per ton of ship capacity, and the average Atlantic passage from all African regions lasted just over two months. (A Brief Overview of the Trans-Atlantic Slave Trade)
Across the approximate 1501–1867 period, between 12% and 13% of captives embarked did not survive the voyage. The methodology table gives a 12.1% mortality estimate for all Africa when measured from embarked captives to those arriving. It gives a higher 14.8% figure when mortality is measured from embarked captives to those disembarked. These percentages use different outcome definitions, so they should be compared as stated rather than collapsed into a single rate. (A Brief Overview of the Trans-Atlantic Slave Trade; The Trans-Atlantic Slave Trade Database)
The methodology table reports regional variation as well. Mortality for the Bight of Biafra was 18.8% when measured from embarked captives to those arriving. Southeast Africa had a 19.5% mortality estimate under the same measure. These are database mortality-sample figures, not a claim that every voyage from either region experienced the same outcome. (The Trans-Atlantic Slave Trade Database)