5. This Is Us - NBC - 16,594,000 Viewers
Sometimes people just need to have a good cry - and NBC's family drama This Is Us is here to help. The series follows the Pearson family through different time frames, gradually unravelling mysteries and answering key questions - like the question of how Jack Pearson, the father of the show's three kids, died. This Is Us has gone from strength to strength, becoming not only one of the most-watched shows on TV but also one of the most talked-about, with fans sharing their theories online and reacting to the sometimes-heartbreaking twists and turns. This Is Us will return for the second half of season 3 in January 2019.
4. NCIS - CBS - 16,724,000 Viewers
Currently in its 16th season, NCIS' average number of viewers has dropped slightly since 2017, but it has climbed up one spot in Nielsen's rankings. The police procedural stars Mark Harmon as a special agent leading a team in the Naval Criminal Investigative Service, which looks into crimes involving Navy or Marine personnel. NCIS is NBC's most-watched drama series of 2018, and has led to two spinoff shows set in New Orleans and Los Angeles. With well over 200 episodes having now aired and ratings still going strong, NCIS is unlikely to end any time soon.
3. The Big Bang Theory - CBS - 18,330,000 Viewers
Geek sitcom The Big Bang Theory is now in its twelfth and final season, and when it reaches its series finale in 2019 it will definitely be going out on a high note. The season premiere drew almost 13 million live viewers, with an average of 18.3 million viewers total checking in to see the antics of Leonard and the gang on Thursday nights this season, holding steady from last year. Don't be surprised if the last episode ever of The Big Bang Theory propels the show to an even higher ranking in 2019's end-of-year stats. By the end of its run - which will come in May 2019 - The Big Bang Theory will be the longest-running multicamera series in the history of television, with 279 episodes total.
2. Sunday Night Football - NBC - 19,560,000 Viewers
TV shows may come and go, but football never dies, and NBC's regularly-programmed Sunday Night Football was the second most-watched show of 2018 - slightly down from its #1 spot in 2017, but with more average viewers than last year. In fact, this year Sunday Night Football broke a ratings record with the Week 9 game between the New England Patriots and Green Bay Packers, with the Patriots beating the Packers 31-17, which attracted almost 18 million live viewers (not including streaming).
1. Roseanne - ABC - 19,960,000 Viewers
It may have been short-lived, but the revival of ABC sitcom Roseanne made a big impression while it was here. Roseanne Barr and John Goodman returned as Roseanne and Dan Conner, with Laurie Metcalf, Gilbert, Lecy Goranson, and Michael Fishman also returning to their roles. The season 10 premiere was watched by a staggering 27.3 million viewers and Roseanne was renewed for an 11th season mere days later. However, the show was cancelled just a few months later following a racist remark on Twitter by Barr, and was re-revived as The Conners - a spinoff series in which family matriarch was killed off and the focus was shifted to the rest of the Conners.