Poster teaser untuk film ini diumumkan pada acara [[CinemaCon]] tahun 2022. Trailer pertama dirilis pada tanggal 11 Oktober 2022, dengan ditemani lagu "[[It's Nice to Have a Friend]]" karya [[Taylor Swift]]. Setelah penayangannya, tarian M3GAN memperoleh perhatian luas melalui media sosial seperti [[TikTok]]. [[Pemasaran viral|Fenomena]] ini membantu membangun antusiasme terhadap perilisan film.<ref>{{Cite web |last=Grebey |first=James |date=January 5, 2023 |title=The story behind M3GAN's iconic TikTok dance sequence |url=https://www.syfy.com/syfy-wire/m3gan-tiktok-dance-sequence-explained |access-date=January 8, 2023 |website=[[Syfy]] |archive-date=January 8, 2023 |archive-url=https://web.archive.org/web/20230108173411/https://www.syfy.com/syfy-wire/m3gan-tiktok-dance-sequence-explained |url-status=live }}</ref><ref>{{Cite web |last=D'Alessandro |first=Anthony |date=January 8, 2023 |title='M3GAN' Slays With $30M+ Opening; 'Avatar: The Way Of Water' Hits Half Billion Faster Than 'Top Gun 2', 'Rogue One' – Sunday AM Box Office Update |url=https://deadline.com/2023/01/box-office-m3gan-avatar-the-way-of-water-1235212918/ |access-date=January 8, 2023 |website=[[Deadline Hollywood]] |archive-date=January 8, 2023 |archive-url=https://web.archive.org/web/20230108015724/https://deadline.com/2023/01/box-office-m3gan-avatar-the-way-of-water-1235212918/ |url-status=live }}</ref><ref name="deadlineJan8" /> Trailer kedua dan terakhir dirilis pada tanggal 7 Desember 2022, dengan ditemani lagu "[[Dolls (lagu)|Dolls]]" karya [[Bella Poarch]]. Dalam film akhir, M3GAN tampil menari dengan lagu "Walk the Night" karya [[Skatt Brothers]].<ref>{{Cite web |last=Daly |first=Rhian |date=January 12, 2023 |title=The Skatt Bros' 'Walk The Night' Soundtracks Hit New Horror Movie 'M3GAN' |url=https://www.udiscovermusic.com/news/the-skatt-bros-walk-the-night-soundtracks-horror-movie-m3gan/ |access-date=16 January 2023 |website=UDiscoverMusic |publisher=[[Universal Music Group]] |archive-date=January 16, 2023 |archive-url=https://web.archive.org/web/20230116080018/https://www.udiscovermusic.com/news/the-skatt-bros-walk-the-night-soundtracks-horror-movie-m3gan/ |url-status=live }}</ref> Pada tanggal 8 Januari 2023, Williams mengungkapkan bahwa ia dan tim pemasar Universal melakukan diskusi tentang apakah adegan tersebut harus dimasukkan dalam trailer atau disimpan untuk ditonton pada saat penayangan film di bioskop. Ia mengatakan kepada ''The Hollywood Reporter'', "Saat kami melihat potongan pertama dari trailer, kami semua melakukan diskusi tentang apakah tarian itu harus ditampilkan dalam trailer atau dicoba disimpan sebagai kejutan dalam film... Dan ternyata, tim pemasar Universal benar untuk tetap menyimpannya dalam trailer, karena hal ini sangat membantu, sejujurnya."<ref>{{Cite web |last=Davids |first=Brian |date=January 6, 2023 |title='M3GAN' Star Allison Williams Talks Her Blumhouse Good Fortune and the Internal Debate Over M3GAN's Viral Dance |url=https://www.hollywoodreporter.com/movies/movie-features/m3gan-star-allison-williams-talks-her-blumhouse-good-fortune-and-the-internal-debate-over-m3gans-viral-dance-1235292567/ |access-date=January 8, 2023 |website=[[The Hollywood Reporter]] |archive-date=January 7, 2023 |archive-url=https://web.archive.org/web/20230107202320/https://www.hollywoodreporter.com/movies/movie-features/m3gan-star-allison-williams-talks-her-blumhouse-good-fortune-and-the-internal-debate-over-m3gans-viral-dance-1235292567/ |url-status=live }}</ref>
