Jaffa Cakes are a cake introduced by McVitie and Price in the UK in 1927 and named after Jaffa oranges. The most common form of Jaffa cakes are circular, 2+1⁄8 inches (54 mm) in diameter and have three layers: a Genoise sponge base, a layer of orange flavoured jam and a coating of chocolate. Each cake is 46 calories. Jaffa Cakes are also available as bars or in small packs, and in larger and smaller sizes. The original Jaffa Cakes now come in packs of 10, 20, 30, or 40, having been downsized in 2017 from 12 or 24 per pack.

Because McVitie's did not register the name "Jaffa Cakes" as a trademark, other biscuit manufacturers and supermarkets have made similar products under the same name. The product's classification as a cake or biscuit was part of a VAT tribunal in 1991, with the court finding in McVitie's favour that Jaffa Cakes should be considered cakes and not biscuits for tax purposes. In 2012 they were ranked the best selling cake or biscuit in the United Kingdom.

McVitie's entire line of Jaffa Cakes are produced at the McVitie's factory in Stockport. The Jaffa cake production area covers an acre (44,000 sq ft; 4,000 m) and includes a production line over a mile (1.6 km) long. In the early 2000s, it pioneered the development of advanced machine vision technology for quality control.

Although Jaffa Cakes are usually orange flavour, limited edition flavours have been available, such as lemon-and-lime, strawberry and blackcurrant. McVities launched limited-edition pineapple flavour Jaffa Cakes in early 2020. In early 2021, McVitie's unveiled the new flavours cherry and passionfruit. In mid 2023, McVitie's launched Raspberry flavour Jaffa Cakes. In June 2024, McVitie's launched Cola Bottle flavour Jaffa Cakes.

In the United Kingdom, value added tax is payable on chocolate-covered biscuits, but not on chocolate-covered cakes. McVities defended its classification of Jaffa Cakes as cakes at a VAT tribunal in 1991, against the ruling that Jaffa cakes were biscuits due to their size and shape, and the fact that they were often eaten in place of biscuits. McVities insisted that the product was a cake, and produced a giant Jaffa Cake in court to illustrate its point.

The court discounted the expert evidence, as it went beyond the capacity of an ordinary purchaser.

The product was assessed on the following criteria:

• The product's name was regarded as a minor consideration.
• The ingredients were regarded as similar to those of a cake, producing a thin cake-like mixture rather than the thick dough of a biscuit.
• The product's texture was regarded as being that of a sponge cake.
• The product hardens when stale, in the manner of a cake.
• A substantial part of a Jaffa Cake, in terms of bulk and texture, is sponge.
• In size, a Jaffa Cake is more like a biscuit than a cake.
• The product was generally displayed for sale alongside other biscuits, rather than with cakes.
• The product is presented as a snack and eaten with the fingers, like a biscuit, rather than with a fork as a cake might be. The tribunal also considered that children would eat them in a few mouthfuls, in the manner of a sweet.

The court was adjudicated by Mr Donald Potter QC, who found in favour of McVitie's and ruled that whilst Jaffa Cakes had characteristics of both cakes and biscuits, the product should be considered a cake and not a biscuit, meaning that VAT is not paid on Jaffa Cakes in the United Kingdom.

The Irish Revenue Commissioners also regard Jaffa Cakes as cakes, since their moisture content is greater than 12%. As a result, they are charged the reduced rate of VAT (13.5% as of 2016).

In 2021, artificially intelligent binary classifiers "usually used in the field of astronomy" were trained on 92 traditional recipes of cakes and biscuits and determined Jaffa Cakes to be cakes.

In 2021 McVities launched £4.7 million advertising and social media campaign to promote the brand.

• Mondelez brand Lefèvre-Utile (LU) produced Jaffa Cakes under the commercial name PiM's. The jam flavours include cherry, orange, pear, raspberry, lemon, chocolate mousse and hazelnuts, etc.
• Delicje Szampańskie are the Polish equivalent and had been manufactured by E. Wedel since 1977. As of 2020, Delicje brand belongs to Mondelēz International, Inc.
• Jaffa Crvenka produces Jaffa Cakes in Serbia.
• Mondelez Czech Republic s.r.o. distributes this type of product under the traditional Slovak chocolate brand Figaro in Czechia and Slovakia with the name "Čoko Piškoty" or čokopiškoty (= chocolate sponge bisquits) in 5 flavour variants. The names "PiM's" or "Jaffa cakes" are not very familiar in Czechia and Slovakia, but rarely also used. It was also distributed by Mondelez under the Czech-Silesian chocolate brand Opavia or German brand Milka.