As with most Star Trek shows, Star Trek: Voyager had certain seasons that were better than others in its seven season run. Voyager was the fourth television series in the Star Trek franchise and ran congruently with Star Trek: Deep Space Nine, premiering in January 1995 and ending in May 2001 for a total of 172 episodes. The show was notable for introducing many popular characters including Captain Kathryn Janeway (Kate Mulgrew) and Seven of Nine (Jeri Ryan), and maintains a devoted following among Star Trek fans today.
Star Trek: Voyager's overarching plot about the crew attempting to return home after being stranded in the Delta Quadrant created numerous opportunities for great storytelling. Voyager introduced new sci-fi challenges and alien races to a well-established franchise, while still taking the opportunity to explore already popular Star Trek aliens, concepts, and characters. Like any TV show, however, Voyager included a mix of episodes in terms of quality, some that were well-crafted and executed, others less so. These episodes, in turn, added up to make certain seasons of the show better than others, creating a definitive hierarchy of Voyager's seasons that can clearly be seen when the show is looked at as a whole.
7 Season 2
Season 2 of Star Trek: Voyager got off to a rocky start from the beginning, with four episodes originally intended for the end of season 1 being moved to the beginning of season 2. This created an underwhelming Star Trek premiere episode in "The 37's" which saw the crew discovering a planet inhabited by humans abducted from Earth in 1937, including Amelia Earhart (Sharon Lawrence). While the concept might have been executed better under other circumstances, issues with the writing and production of the episode caused the plot to feel a bit contrived and left lingering, unanswered questions that hurt the episode as a whole.
Season 2 of Star Trek: Voyager also included some of the worst-reviewed episodes of the series, such as "Elogium" and "Threshold". "Threshold", in particular, continues to be one of the most divisive episodes in the whole Star Trek franchise, with a plot revolving around Tom Paris' (Robert Duncan McNeill) transformation into a salamander-like creature after he breaks the Warp 10 speed barrier. The episode ends with him and a likewise-transformed Captain Janeway mating and creating offspring on an unknown planet after Paris abducts her. While some episodes were better, including one introducing John de Lancie's Q to Star Trek: Voyager, season 2 is the worst season of the series when looked at collectively.
6 Season 3
While it didn't have as many divisive episodes as season 2, season 3 of Star Trek: Voyager still struggled to make a big impact on the series. The season did include a number of episodes that connected Voyager more concretely to the wider Star Trek universe. The episode "Flashback" revealed that Voyager's Vulcan security officer Tuvok (Tim Russ) had served on the USS Excelsior under Captain Hikaru Sulu, with George Takei reprising his iconic role, and episodes like "False Profits", "The Q and the Grey", and "Unity" included such iconic Star Trek aliens as the Ferengi, Q, and the Borg. However, these wider franchise connections weren't enough to carry the episodes they appeared in. Even "Flashback" was not able to become one of Voyager's most memorable episodes despite the popularity of Sulu and Takei.
Season 3 did include a few better episodes in contrast with the bad. "Future's End, Parts I and II" had a well-executed time travel storyline, and guest-starred popular actors Ed Begley Jr. and Sarah Silverman. Likewise, the season finale "Scorpion Part I" definitively introduced the Borg as one of Star Trek: Voyager's main villains and created another truly terrifying villain in Species 8472. The episode's second part, which acted as the season 4 premiere, was when Jeri Ryan's Seven of Nine joined Star Trek: Voyager's cast as a series regular however, meaning that season 3 falls just short of being able to claim the distinction of having introduced such a popular character to the Star Trek franchise.
5 Season 1
Season 1 of Star Trek: Voyager still had its fair share of middling episodes. In particular, Voyager's pilot episode, "Caretaker, Part I and II," is one of the better-reviewed pilots in the Star Trek franchise, eclipsing Star Trek: The Next Generation's pilot, "Encounter as Farpoint" in terms of writing and acting quality. "Caretaker" introduced both a diverse, interesting cast of characters and a compelling overall theme for Voyager, and allowed the series to branch out into new territory by setting it in a region of space the Star Trek franchise had never explored.
That said, season 1 was also Star Trek: Voyager's shortest, coming in at just 16 episodes instead of the usual 26. Additionally, while Voyager season 1 did include some truly great episodes with solid Star Trek concepts, such as "Heroes and Demons" and "Faces", it suffered from a curse that almost every Star Trek series encountered, and was not able to capture audience attention or acclaim as well as later seasons did. Season 1 was a good introduction to the series, but when compared to other seasons of Voyager, it consistently falls short in terms of episode quality.
4 Season 7
Star Trek: Voyager season 7 ended the show and saw the crew achieve their goal of returning home in its finale "Endgame, Part I and II". While this might seem to indicate a satisfying conclusion, "Endgame" did not end up being a complete success. The episode's use of time travel failed to live up to expectations, and included a baffling (and ultimately failed) romance between Seven of Nine and Robert Beltran's Chakotay, as well as a slightly abrupt ending that left viewers wanting more. "Endgame" ranks right in the middle of other Star Trek series finales overall, and while not the worst-reviewed finale of any series in the franchise, did not hit the mark for many viewers.
The rest of the season also failed to include any particularly iconic episodes outside of the finale. While episodes like "Body and Soul", "Shattered", and "Author, Author" played around with some distinctly Star Trek sci-fi concepts such as body swapping, parallel timelines, and the question of sentience when it comes to inorganic beings, the season as a whole did not add up to more good episodes than bad. Star Trek: Voyager season 7 may have been the show's final outing, but it would not end up being the season that devotees of the show ranked the highest.
3 Season 4
With the introduction of Seven of Nine in Star Trek: Voyager's season 4 premiere, and the establishment of the Borg and the Hirogen as villains for the later half of the series, season 4 saw Voyager truly begin to hit its stride. Seven of Nine, in particular, was given some extremely compelling episodes for her first season with the crew, including "The Gift" and "The Raven" In part because of these episodes, Seven not only became one of the most popular characters on the show but has gone on to become a particular fan-favorite, so much so that she was brought back years after Voyager's finale as a series regular on Star Trek: Picard.
Season 4 also included some truly iconic Star Trek: Voyager episodes, such as the two-parters "Year of Hell" and "The Killing Game", and riveting, dramatic storylines for often underutilized characters like Neelix (Ethan Phillips) in season 4 episodes like "Mortal Coil". While not every episode hit the mark, season 4 was arguably the season that held more successful episodes than any other season before it. This holds true today as well, with specific episodes still ranked consistently higher than others in Voyager's previous seasons.
2 Season 6
Star Trek: Voyager's season 6 ended up being a better entry in the series than the show's final season. Season 6 began with the conclusion of "Equinox", a two-part episode that combined high-stakes drama with a classic Star Trek moral dilemma as Voyager's crew battled against the crew of the USS Equinox, another Star Trek Federation ship stranded like Voyager that was using the murdered bodied of an alien race as a fuel to help them return home faster. With this intense start, season 6 went on to be a mix of incredibly funny, entertaining episodes like "Tinker, Tenor, Doctor, Spy" and extremely well-crafted, poignant plots such as "Blink of an Eye", the highest-rated episode of Voyager according to IMDb.
While episodes like "Fair Haven" and its sequel "Spirit Folk" are often ranked low by critics and viewers, season 6 of Voyager maintained a comfortable level of popular episodes during its run. The season also included cameos from two iconic Star Trek: The Next Generation characters, Lt. Reginald Barclay (Dwight Schultz) and Counselor Deanna Troi (Marina Sirtis), once again finding an entertaining way to connect Voyager to the wider Star Trek franchise. While not the absolute best season of Star Trek: Voyager, season 6 is a close second.
1 Season 5
With a cadre of high-quality episodes that flow well together, season 5 of Star Trek: Voyager is generally considered the series' best season overall. Season 5 included such memorable episodes as "Timeless", the 100th episode of Voyager, and a tour de force for Garrett Wang's Ensign Harry Kim as future versions of himself and Chakotay rush to prevent a piloting accident from causing Voyager's entire crew to perish in a deadly crash. Like season 4, season 5 was also an important season for Seven of Nine, with episodes like "Drone", "Dark Frontier Part I and II", and "Relativity" allowing Jeri Ryan's acting talents to shine.
Classic Star Trek holodeck accident episodes such as "Bride of Choatica!", and thought-provoking episodes centered around Robert Picardo's The Doctor like "Latent Image" meant that season 5 included something for everyone in terms of entertainment. Although the season still had episodes that didn't perform as well, these were much fewer and farther between than in previous seasons. Star Trek: Voyager took a bit of time to find what worked and what didn't for the series, but many of the later seasons, and season 5 in particular, ended up being Voyager's best entries into the Star Trek franchise.