Saint John the Baptist is the patron saint of the Commonwealth of Puerto Rico and its capital city, San Juan. In 1521, the island was given its formal name, "San Juan Bautista de Puerto Rico", following the custom of christening a town with its formal name and the name which Christopher Columbus had originally given the island. The names "San Juan Bautista" and "Puerto Rico" were eventually used in reference to both city and island, leading to a Reversal in terminology by most inhabitants largely due to a cartographic error. By 1746, the city's name ("Puerto Rico") had become that of the entire island, while the name for the island ("San Juan Bautista") had become that of the city. The official motto of Puerto Rico also references the saint: Joannes Est Nomen Eius (Latin for "his name is John", from Luke 1:63).

In addition to the above, 5 September is the commemoration of Zechariah and Elizabeth, Saint John's parents. The Russian Orthodox Church observes 12 October as the Transfer of the Right Hand of the Forerunner from Malta to Gatchina (1799).

The LDS Church teaches that John the Baptist appeared on the banks of the Susquehanna River near Harmony Township, Susquehanna County, Pennsylvania as a resurrected being to Joseph Smith and Oliver Cowdery on May 15, 1829, and ordained them to the Aaronic Priesthood. According to LDS doctrine, John's ministry has operated in three dispensations: he was the last of the Prophets under the law of Moses; he was the first of the New Testament prophets; and he was sent to confirm the Aaronic Priesthood in our day (the dispensation of the fulness of times). Mormons believe John's ministry was foretold by two Prophets whose teachings are included in the Book of Mormon: Lehi and his son Nephi.

The burial-place of John the Baptist was traditionally said to be at the Nabi Yahya Mosque (Saint John the Baptiste Mosque) in Sebaste in current Palestinian territories, and mention is made of his relics being honored there around the middle of the 4th century. The historians Rufinus and Theodoretus record that the shrine was desecrated under Julian the Apostate around 362, the bones being partly burned. A portion of the rescued relics were carried to Jerusalem, then to Alexandria, where on 27 May 395, they were laid in the basilica newly dedicated to the Forerunner on the former site of the temple of Serapis. The tomb at Sebaste continued, nevertheless, to be visited by pious pilgrims, and Saint Jerome bears witness to miracles being worked there.

John the Baptist has appeared in a number of screen adaptations of the life of Jesus. Actors who have played John include Robert Ryan in King of Kings (1961), Mario Socrate in The Gospel According to St. Matthew (1964), Charlton Heston in The Greatest Story Ever Told (1965), David Haskell in Godspell (1973), Michael York in Jesus of Nazareth (1977), and Andre Gregory in The Last Temptation of Christ (1988).

Also, on the night of June 23 on to the 24th, Saint John is celebrated as the patron saint of Porto, the second largest city in Portugal. An article from June 2004 in The Guardian remarked that "Porto's Festa de São João is one of Europe's liveliest street festivals, yet it is relatively unknown outside the country".

Another obscure claim relates to the town of Halifax in West Yorkshire, United Kingdom, where, as patron saint of the town, the Baptist's head appears on the official coat-of-arms. One legend (among others) bases the etymology of the town's place-name on "halig" (holy) and "fax" (face), claiming that a relic of the head, or face, of John the Baptist once existed in the town.
Also, in 2010, bones were discovered in the ruins of a Bulgarian church in the St. John the Forerunner Monastery (4th–17th centuries) on the Black Sea island of St. Ivan and two years later, after DNA and radio carbon testing proved the bones belonged to a Middle Eastern man who lived in the 1st century AD, Scientists said that the remains could conceivably have belonged to John the Baptist. The remains, found in a reliquarium are presently kept in the Sts. Cyril and Methodius Cathedral in Sozopol.

As a child (of varying age), he is sometimes shown from the 15th century in family scenes from the life of Christ such as the Presentation of Christ, the Marriage of the Virgin and the Holy Kinship. Leonardo da Vinci's versions of the Virgin of the Rocks were influential in establishing a Renaissance fashion for variations on the Madonna and Child that included John, probably intended to depict the relative's reunion in Egypt, when after Jesus' FLIGHT to Egypt John was believed to have been carried to join him by an angel. Raphael in particular painted many compositions of the subject, such as the Alba Madonna, La belle jardinière, Aldobrandini Madonna, Madonna della seggiola, Madonna dell'Impannata, which were among his best-known works. John was also often shown by himself as an older child or adolescent, usually already wearing his distinctive dress and carrying a long thin wooden cross – another theme influenced by Leonardo, whose equivocal composition, reintroducing the camel-skin dress, was developed by Raphael Titian and Guido Reni among many others. Often he is accompanied by a lamb, especially in the many Early Netherlandish paintings which needed this attribute as he wore normal clothes. Caravaggio painted an especially large number of works including John, from at least five largely nude youths attributed to him, to three late works on his death – the great Execution in Malta, and two sombre Salomes with his head, one in Madrid, and one in London.

His birth, which unlike the Nativity of Jesus allowed a relatively wealthy domestic interior to be shown, became increasingly popular as a subject in the late Middle Ages, with depictions by Jan van Eyck in the Turin-Milan Hours and Ghirlandaio in the Tornabuoni Chapel being among the best known. His execution, a church feast-day, was often shown, and by the 15th-century scenes such as the dance of Salome became popular, sometimes, as in an engraving by Israhel van Meckenem, the interest of the Artist is clearly in showing the life of Herod's court, given contemporary dress, as much as the martyrdom of the saint. Salome bearing John's head on a platter equally became a subject for the Northern Renaissance taste for images of glamorous but dangerous women (Delilah, Judith and others), and was often painted by Lucas Cranach the Elder and engraved by the Little Masters. These images remained popular into the Baroque, with Carlo Dolci painting at least three versions. John preaching, in a landscape setting, was a popular subject in Dutch art from Pieter Brueghel the Elder and his successors.

Amiens cathedral, which holds one of the alleged heads of the Baptist, has a biographical sequence in polychrome relief, dating from the 16th century. This stresses the execution and the disposal of the saint's remains.

John is believed to have had the specific role of foretelling and preparing the way for Jesus. In condemning those who had ‘turned aside’ from him, Bahá'u'lláh, compared them to the followers of John the Baptist, who, he said, ‘protested against Him Who was the Spirit (Jesus) saying: “The dispensation of John hath not yet ended; wherefore hast thou come?” Bahá'u'lláh believed that the Báb played the same role as John in preparing the people for his own coming. As such Bahá'u'lláh refers to the Báb as ‘My Forerunner’, the Forerunner being a title that Christians reserve for John the Baptist. However, Bahá'ís consider the Báb to be a greater Prophet (Manifestation of God) and thus possessed of a far greater station than John the Baptist.

A remarkable Pre-Raphaelite portrayal is Christ in the House of His Parents by John Everett Millais. Here the Baptist is shown as a child, wearing a loin covering of animal skins, hurrying into Joseph's carpenter shop with a bowl of water to join Mary, Joseph, and Mary's mother Anne in soothing the injured hand of Jesus. Artistic interest enjoyed a considerable revival at the end of the 19th century with Symbolist Painters such as Gustave Moreau and Puvis de Chavannes (National Gallery, London). Oscar Wilde's play Salome was illustrated by Aubrey Beardsley, giving rise to some of his most memorable images.