[10] Throughout training camp, Herndon competed to be the starting tight end against Eric Tomlinson, Clive Walford, Neal Sterling, and Jordan Leggett.
[11] Head coach Todd Bowles named Herndon the fourth tight end on the depth chart to begin the regular season, behind Tomlinson, Sterling, and Leggett.
[15] On December 23, 2018, he caught six passes for a season-high 82 receiving yards and scored a touchdown as the Jets lost 44–38 against the Green Bay Packers in Week 16.
[16] Herndon gradually became the Jets’ primary receiving tight end during the season and surpassed Neal Sterling and Jordan Leggett on the depth chart.
[citation needed] He was named to Pro Football Writers of America All-Rookie Team, becoming the fourth Jets tight end to receive this award, joining Johnny Mitchell (1992), Anthony Becht (2000), & Jace Amaro (2014).