This is a great series that has remained at the top of the charts due to their amazing story that has managed to perfectly balance action, comedy, a meaningful plot with great character development. It is also one of the very few animes that actually has an ending, and one of the best endings of any story!

If you are wondering if you should watch  FMA or  FMAB, or both, well, the truth is that in order to get the full manga story you'll need to watch both for the best experience, especially if this is your first time watching.

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The Dub is excellent for both series.

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HOW TO WATCH:

1. Watch The Full Manga Story

FMA is better with the beginning of the story, which FMAB condenses too much (in less than 8 episodes), so you don't get the same emotional immersion. For example, if you would like to know why Shou Tucker has remained the top hated character since 2003, you'll have to watch the FMA 2003 version first, as FMAB just recaps the event in one episode. And this is one of the major events that shape the lives of the main protagonists, but it will pass you by if you just watch the FMAB version, and it will spoil the story if you decide to watch FMA later. FMAB has a better ending, as it's the manga ending created by the original author.

Therefore, this is my favorite way of watching the series as it's the full manga story encompassing the best parts of both shows. Note that watching this way won't spoil anything if you decide to watch each series in full later. However, note that you might notice some slight differences in some character's personalities. In this case, the order will be:

• Watch Fullmetal Alchemist (2003) Episodes 1-3 
• Optional Fullmetal Alchemist (2003) Filler Episode 4 
  • This is an extra mission, not essential to the main story. It's a tale of "real love" vs. obsession with physical attraction. I think is good & memorable, but it can be watched at a later time.
• Watch Fullmetal Alchemist (2003) Episodes 5-9 
  • This contains the infamous Shou Tucker Arc!
• Optional Fullmetal Alchemist (2003) Filler Episode 10 
  • This is just comedic relief, non-essential to the main plot. I think is a fun episode, but you can skip with no issues if you don't like it, or if you just want to speed up the main plot.
• Optional Fullmetal Alchemist (2003) Episodes 11-12 
  • This is an adaptation from the light novel Fullmetal Alchemist: The Land of Sand, rather than the manga.
  • These episodes are ok, they help to expand the world & ideology, but they are not essential to the main plot. So it's a side story or extra mission that can be watched at any time.
  • These characters have a cameo appearance after Episode 26 of FMA, so you may want to watch these episodes first if you are watching the Filler Story.
• Watch Fullmetal Alchemist (2003) Episodes 13-25 
  • These episodes contain some filler but they are necessary for the continuation of the story.
  • Ignore the line "we want you to make us human", this is only relevant to the Filler Story, as this works differently in the manga.
• Skip Fullmetal Alchemist (2003) Episodes 26-51 
  • This is where the stories start to diverge considerably, and the best point to jump to Brotherhood.
• Skip Brotherhood Episodes 1-10
  • These episodes condense what you saw in FMA, some events are slightly different, but it's condensed too much like a recap, so you don't get the same emotional engagement as in FMA, reason why I still recommend you watch that first.
• Watch Brotherhood Episodes 11-26
  • Note that Episode 11 continues at the exact point you left the story from FMA at Episode 25 (when they arrived at their destination after taking the train).
  • The event with the Alchemist's Watch will be repeated in a different form, but other than that you won't see any other significant discrepancies in the story.
• Watch Brotherhood Episode 2
  • Watch between Brotherhood Episodes 26 & 27 (Between P2-E13 & P3-E01 on Netflix) You could watch this earlier if you prefer, but this is an excellent point to insert this episode within the continuity of the story.
  • This is a flashback that expands on the story of how the Elric brothers learned alchemy, shows their mom's death and what happened while performing human transmutation, then goes into how Edward decided to become a state alchemist. It's rather essential to mark the differences in how the rules of the world differ between FMA & FMAB.
• Watch Brotherhood Episodes 27-64 
• Optional Brotherhood Episode 1
  • This is a side story, an extra mission to hunt down the "Freezing Alchemist", which was not featured in FMA. It can be watched at any time as it's not essential to the main story.
• Optional Brotherhood Episodes 3-10
  • You only want to watch these episodes if you are curious about the differences between FMA & FMAB.

Watch at the end of Brotherhood.

These are good side stories, some expand on events that were not shown in the series, including backstories of 'The Teacher' Izumi, Mustang's & Hughes' past.

Optional side story, not in the main timeline, but it's an ok watch.

It's best to leave at the end of the Brotherhood series and consider it independent of the main story, since it takes what we knew about the way philosopher's stones worked, and rewrites it, rather than adding to it. Is for this reason some people don't like the movie at all.

The dub is good.

Skip, they are just pathetic comedic relief with awful animation.

2. Watch The Filler Story

The filler story is not bad, it's just not as good as the manga story. They use the same characters and they have the same personalities with some slight differences, but the events, the antagonist, and the main focus differ from the original manga story, the way alchemy works is also different, as well as some character's roles.

FMA story is about redemption, trying to fix their mistakes while FMAB is about learning to stand by yourself and don't depend on magic or miracles to fix your problems.

FMA is better at the first part, which FMAB, condenses too much, in less than 10 episodes, so you don't get the same emotional immersion. FMA ending is ok, FMAB ending it's outstanding, but in my opinion, both stories are worth watching. FMAB closely follows the manga.

Both stories have themes of war, crime, scientific progress, the real value of life, and taking responsibility for your actions. These series are a must-watch and I think everyone will enjoy them.

1. Watch Fullmetal Alchemist (2003) 
   1. Episodes 1-25 are faithful to the manga. 
      • You may want to review the Optional notes on the Manga Story Guide above to decide what to watch from these episodes.
   2. The Filler Story starts in Episode 26.
2. Watch The Movie: Conqueror of Shamballa This is the sequel & conclusion to FMA 2003 Filler Story.

If you want to see a more in-depth comparison between the manga and both anime adaptations you can watch this video, just know that it contains spoilers.

Differences with Brotherhood (Contains Spoilers)

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Regarding as Why to Watch FMA, this is an extract from sothis review:

"Full Metal Alchemist is, in a word, brilliant. It's hard to explain exactly why it was so good, so you'd probably just have to see it for yourself. There is a perfect blend of comedy, action, intrigue and excitement all in one. Filler episodes are wonderful and fly by quicker than a bullet train. I never at any point in the series was bored, even for a second. In the beginning, there are a great deal of mini-arcs that deal with events in a certain town or location, but all are still somewhat involved with the main plot. Once the end of the series rolls around, you realize that all of these seemingly unconnected events or places really ARE connected, or come back into play somehow. This comes down to FMA's epic nature at heart, and maybe that's why it was so good, who knows. 

FMA is an extremely dark series, with plenty of very messed up scenes and ideas. "Wow" came to mind many a time when something gruesome happened yet again, and this continues throughout the entire series. There are plenty of twists and turns along the way (with one really major one near the end), most of which will surprise you and catch you off guard. There is also a plethora of character development and characters in general, all of whom have a rich background and history. The empathy we feel when a character is killed, for example (or hurt in any way) is present throughout the entire series because of how well the character interactions were presented in tandem with the plot. Truly, there aren't enough good things I can say about the story... it reels you in in the first few episodes and holds on tight till the final act (which is a very beautiful yet open ending, setting itself up nicely for the movie). There are barely any series I see that make me want to watch the next episode so badly, and this is one of them, for 51 episodes in a row. A 10? Can't give it anything less.

I can't say enough good things about this series, but I feel like watching it for yourself would make you understand why I gave it a perfect score. Everything about the series is flawless, from the epic and involved story to the pacing and mood, to the music and animation and depth of characters. It really is rare for a series like this to come along that not only succeeds at keeping your attention for 26 episodes, but for 51. What are you waiting for? Check this out as soon as you can." -sothis

Watch. This is the Sequel & Ending to the FMA 2003 Filler Story.

Skip, this is just a Recap.

Skip, these are just boring explanations of some concepts of their world and short stories that are mostly comedic relief or slice-of-life.

Skip, this is just silly comic relief.