Nabisco (/nəˈbɪskoʊ/, abbreviated from the earlier name National Biscuit Company) is an American manufacturer of cookies and snacks headquartered in East Hanover, New Jersey. The company is a subsidiary of Illinois-based Mondelēz International.

Nabisco's 1,800,000-square-foot (170,000 m) plant in Chicago is the largest bakery in the world, employing more than 1,200 workers and producing around 320 million pounds (150 million kilograms) of snack foods annually. Its products include Chips Ahoy!, Belvita, Oreo cookies, Ritz Crackers, Teddy Grahams, Triscuit crackers, Fig Newtons, and Wheat Thins for the United States, United Kingdom, Mexico, Bolivia, Venezuela, and other parts of South America.

All Nabisco cookie or cracker products are branded Christie in Canada, after Canadian baker William Mellis Christie. Christie's flagship bakery in Toronto was demolished after Mondelēz shut it down in 2013. Nabisco opened corporate offices as the National Biscuit Company in the Home Insurance Building in the Chicago Loop in 1898, the world's first skyscraper.

Pearson & Sons Bakery opened in Massachusetts in 1792, and they made a biscuit called pilot bread for consumption on long sea voyages. In 1889, William H. Moore acquired Pearson & Sons Bakery, Josiah Bent Bakery, and six other bakeries to start the New York Biscuit Company. Chicago lawyer Adolphus Green (1843–1917) started the American Biscuit and Manufacturing Company in 1890 after acquiring 40 different bakeries. Then Moore, Green, and John Gottlieb Zeller (1849–1939, founder of Richmond Steam Bakery) all merged in 1898 to form the "National Biscuit Company", and Green was named president. Zeller was president of National Biscuit Company from 1923–1931.

Nabisco celebrated its golden anniversary in 1948, and Nabisco had become the corporate name by 1971. In 1981, Nabisco merged with Standard Brands to form "Nabisco Brands", which merged with R. J. Reynolds Tobacco Company in 1985 to form RJR Nabisco. Kraft General Foods acquired the Nabisco cold cereals from RJR Nabisco in 1993, and the cereal brands are now owned by Post Holdings. In 1999, Nabisco acquired Favorite Brands International. In 2000, Philip Morris Companies Inc. acquired Nabisco and merged it with Kraft Foods in one of the largest mergers in the food industry. In 2011, Kraft Foods announced that it was splitting into a grocery company and a snack food company. Nabisco became part of the snack-food business, which took the name Mondelēz International.

The first use of the name Nabisco was in a cracker brand produced by National Biscuit Company in 1901. The firm later introduced Fig Newtons, Nabisco Wafers, Anola Wafers, Barnum's Animal Crackers (1902), Cameos (1910), Lorna Doones (1912), Oreos (1912), and Famous Chocolate Wafers (1924, which would be discontinued in 2023).

In 1924, the National Biscuit Company introduced a snack in a sealed packet called the Peanut Sandwich Packet. They soon added the Sorbetto Sandwich Packet. These allowed salesmen to sell to soda fountains, road stands, milk bars, lunch rooms, and news stands. Sales increased, and the company started to use the name NAB in 1928. The term Nabs today is used to generically mean any type of snack crackers, most commonly in the southern US.

As of July 16, 2021, parent company Mondelēz International made the decision to close the Fair Lawn plant after 63 years forcing the majority of the 600 employees to move on and/or retire, accept jobs with other businesses or transfer within the company.

In August 2021, over 1,000 workers at several bakeries and distribution centers throughout the United States, organized under the Bakery, Confectionery, Tobacco Workers and Grain Millers' International Union, went on strike over disagreements regarding a new labor contract with Nabisco.

The National Biscuit Company acquired the Shredded Wheat Company, maker of Triscuit and Shredded Wheat cereal, and Christie, Brown & Company of Toronto in 1928, but all of the Nabisco cookie and cracker products in Canada still use the name Christie. It also acquired F.H. Bennett Company, maker of Milk-Bone dog biscuits, in 1931.

In 1971, Nabisco bought J. B. Williams Co., a privately-owned pharmaceuticals manufacturer. Williams continued to operate as a separate subsidiary. Nabisco sold Williams to Beecham Group in 1982 after nearly a decade of slumping sales.

In 1981, Nabisco merged with Standard Brands, maker of Planters Nuts, Baby Ruth and Butterfinger candy bars, Royal gelatin, Fleischmann's and Blue Bonnet margarines, amongst others. The company was then renamed Nabisco Brands, Inc. At that time, it also acquired the Life Savers brand from the E.R. Squibb Company, makers of Bubble Yum & Care-free gum. Commercials were revised as a result of the merger by January 1983.

In 1985, Nabisco was bought by R.J. Reynolds, forming "RJR Nabisco". After three years of mixed results, the company became one of the hotspots in the 1980s leveraged buyout mania. The company was in auction with two bidders: F. Ross Johnson, the company's president and CEO, and Kohlberg Kravis Roberts, a private equity partnership.

The company was sold to KKR in what was then the biggest leveraged buyout in history, described in the book Barbarians at the Gate: The Fall of RJR Nabisco, and a subsequent film.

In 1989, RJR Nabisco Inc. sold its Chun King foods division to Yeo Hiap Seng Limited and Fullerton Holdings Pte. Ltd for $52 million to reduce its debt from its $24.5 billion buyout by Kohlberg Kravis Roberts & Co.

In December 1989, RJR Nabisco sold its Del Monte canned fruits and vegetables business in South America to Polly Peck International PLC. One year later, in 1990 RJR Nabisco sold Curtiss Candy, which owned the Baby Ruth and Butterfinger brands, to Nestlé. RJR also sold LU, Belin and other European biscuit brands to Groupe Danone, only reunited in 2007 after Nabisco's present parent, Kraft Foods, bought Danone's biscuit operations for €5.3 billion.

In 1994, RJR sold its breakfast cereal business (primarily the Shredded Wheat franchise) to Kraft Foods Inc. and the international licenses to General Mills, which later became part of the Cereal Partners Worldwide joint venture with Nestlé.

Also in 1994, RJR acquired Rose Knox's Knox gelatin and integrated the Shredded wheat franchise into the Post Foods portfolio. Post continues to sell the product today.

In 1995, Nestlé agreed to buy the Ortega Mexican foods business from Nabisco Inc. That same year, RJR-Nabisco also acquired the North American margarine and table spreads business of Kraft foods. This purchase included Parkay, Touch of Butter and Chiffon.

In 1998, Nabisco Holdings announced its sale of its margarine and egg substitute business to ConAgra. In 1997, the brands of Fleishmann's, Blue Bonnet and Parkay had sales of $480 million. It also sold its College Inn broth brand to HJ Heinz and its Venezuelan Del Monte operations to Del Monte Foods.

In 1999, RJR Nabisco's food and tobacco empire fell apart when they sold its international tobacco division to Japan Tobacco for $7.8 billion.

In 2000 Nabisco Holdings together with several investors (as Finalrealm) acquired United Biscuits, As part of the transaction, United Biscuits acquired Nabisco's European businesses and divested Far East (China, Hong Kong, and Taiwan) business to Nabisco. Nabisco became a leading shareholder in United Biscuits (the position that inherited by Kraft Foods until 2006).

The Altria Group (formerly Philip Morris) acquired Nabisco (sans Bubble Yum which was sold to Hershey) in 2000 for about $19.2 billion. Philip Morris then combined Nabisco with Kraft. That acquisition was approved by the Federal Trade Commission subject to the divestiture of products in five areas: three Jell-O and Royal brands types of products (dry-mix gelatin dessert, dry-mix pudding, no-bake desserts), intense mints (such as Altoids), and baking powder. Kraft Foods, at the time also a subsidiary of Altria, merged with Nabisco.

In 2006, Nabisco sold its Milk-Bone pet snacks to Del Monte Foods Co. for $580 million. Altria spun-off Kraft Food along with its Nabisco subsidiary in 2007. In January 2007, Kraft sold Cream of Wheat to B&G Foods.

In 1997, the National Advertising Division of the Council of Better Business Bureaus became concerned with an ad campaign for Planters Deluxe Mixed Nuts. The initial commercial featured a man and monkey deserted on an island. They discover a crate of Planters peanuts and rejoice in the peanuts' positive health facts.

Nabisco made a detailed statement describing how their peanuts were healthier than most other snack products, going as far as comparing the nutritional facts of Planters peanuts to those of potato chips, Cheddar cheese chips, and popcorn. Technically, the commercials complied with United States Food and Drug Administration regulations, and they were allowed to continue. However, as requested by the National Advertising Division, Nabisco agreed to make fat content disclosure more conspicuous in future commercials.

The company's A1 Steak Sauce was the subject of a suit filed against Arnie Kaye in US District Court on March 13, 1990. Kaye's delicatessen used a homemade sauce called "A2 Sauce," sold in both the International Deli and Stew Leonard's supermarkets in Westport, Connecticut. Summary judgement was rendered on March 18, 1991 by Judge Eginton who found in favor of Nabsico and ordered that they were entitled to recoup all profits from the sale of "A.2." sauce as well as attorney's fees.