NOTE: Only material released on this service first can be listed here, material that was published first or simultaneously in volume form and then added to the service does not belong here.
COVER DATES: Do not add cover dates to these issues as it breaks first appearances.
Shonen Jump is an English language publishing service for digital-only chapters of translated manga. Despite the name, the focus is on Shueisha-published manga generally rather than Shonen Jump specifically. The service has its origins in Viz's long-running Shonen Jump magazine which was a physical magazine in the 00's translating a handful of major franchises that had broken through to Western audiences at the time through their anime adaptations. In the 10's, this magazine was ended and replaced with a digital-only magazine subscription which made it easier to publish more material and stuff that wasn't guaranteed to be popular outside Japan.
At this point Viz began to try and translate the first three chapters of almost every new series in Weekly Shonen Jump (barring some exceptions due to their long-standing stance against ecchi). They also tried to get as close to simulpubbed releases as possible but because they bundled stuff from magazines other than Weekly Shonen Jump into the digital magazine, this meant works like those from Jump SQ were not simulpubbed and a handful of series were released digitally on their website individually rather than part of the Shonen Jump magazine. Viz still prioritized properly licensing things they expected to be popular and that were worth publishing physically so many Weekly Shonen Jump series were dropped completely after three chapters, whether they lasted years in the magazine (Hinomaru Zumo) or weeks (Takuan to Batsu). Some were picked up much later after they became popular enough (like Kimetsu no Yaiba) but were published physically only.
By 2018, Shueisha's digital-publishing had become well-established and it was interested in properly expanding globally which it did in January 2019 with MangaPlus, a service intended to simulpub every single Weekly Shonen Jump series and eventually every Shonen Jump+ series as well. The first and most recent three chapters would be free for everyone and unlike Viz's previous attempts at simultaneous publication where the calendar date matched the date in Japan, the new service would take into account time-zones and release a calendar-date earlier than Japan to make the releases truly simultaneous. This new system would significantly change how Viz (Shueisha's primary partner in the English market) published manga and they were given a month advance to launch their identical service with the same goals, minus the Shonen Jump+ focus specifically and with more region-restrictions for service availability.
So in December 2018, Viz cancelled their digital-only magazine and restructured their digital content into a vault of digital chapters that were able to be read by subscribing to the service. The bulk of the initial content was material they had already published in previous decades from Shueisha, which had always been primarily focused on Weekly Shonen Jump material. Over the years they continued introducing previously published content into the vault including decades-old releases or those that had just been initially published outside the service. The service has also expanded significantly into non-Weekly Shonen Jump works including multiple major serializations from V Jump, Jump SQ, Shonen Jump+ and Weekly Young Jump.
One of the first major transitional phases that took years to resolve was the fact that Viz had been very selective on which manga they picked up, even in their years of translating the first three chapters of nearly everything. The last issue they had published as a digital magazine was 201902 in Japan and the first they released on their new service was 201903 in Japan (the last in a round of three new serializations including Chainsaw Man, ne0;lation and Hell Warden Higuma). While normally they would have likely dropped at least ne0 and Higuma, with the timing they were able to transition smoothly into these being two of the first fully translated new serializations on the service.
However, they had already dropped I'm from Japan and Teenage Renaissance! David from the previous new serialization round and did not pick them back up. They had also dropped Jujutsu Kaisen and Act-Age from early in the year but picked them back up from their current chapter in Japan with a massive gap in untranslated chapters. While the popularity of Shonen Jump was a big part of the industry of scanlators trying to illegally profit off their work, Act-Age and Jujutsu had not been picked up on as potential moneymakers by these groups and uniquely had publication gaps that couldn't even be read by English fans through the less-than-legal scanlation market for months.
These massive publication gaps were also present in several other older franchises from Weekly Shonen Jump that Viz had licensed with intent to publish them fully but had been doing so slowly through physical releases (Kimetsu no Yaiba) or digital chapters outside the Weekly Shonen Jump magazine (Haikyu!!) but these gaps had previously already been filled by the scanlation market this service was intended to replace. Viz only completed filling the gaps on all these serializations after a year-and-a-half. Some major serializations were just left to complete in Japan and never had to be picked up because they had been dropped years earlier like Hinomaru Sumo and Gintama (which had last appeared in the Japanese Weekly Shonen Jump a few months before the launch of this simulpub service but still released its final chapters in the first six months of 2019).
MangaPlus simultaneously posts Viz's chapters for anything they publish but since it attempts to be even more expansive in what it publishes, it outsourced translations for Japan, David and Hinomaru to be similarly simulpubbed on its service but these publication gaps were never filled. Yuuna was unable to be picked up by even Mangaplus as Viz's policy on ecchi meant they had already allowed Seven Seas to license it a year earlier, so the series was never simulpubbed in English. A similar conflict arose years later with Viz refusing to publish the ecchi series Ayakashi Triangle uncensored, the series was then transferred out of Weekly Shonen Jump in Japan and simulpubbed exclusively on Mangaplus instead.
While some one-shots are simulpubbed, this is not the norm and its rare for any particular issue of Weekly Shonen Jump to actually be fully translated. Other represented magazines and digital services are far from fully translated but the service has continued to introduce more serializations from outside Weekly Shonen Jump and recently introduced the idea of serializing old Japanese works with Stone Ocean (previous Jojo parts were published physically as entire volumes and then added retroactively to the digital service). In May 2023, they also introduced a similar but smaller service Viz Manga which focused more on the Shogakukan half of their history.