Asatte no Houkou.

A supernatural tale that takes place in summer. Asatte no houkou is less deep, but gives you a lesson about true friendship, just like in Air.  

Both have a very relaxed, somewhat "slice of life" feel to them, yet still pack an emotional punch. The atmosphere in both can best be described as a "lazy Sunday afternoon" feel. Definitely check out Asatte no Houkou! 

The two main characters switch ages- One becomes a kid and the other becomes an adult. The atmosphere is the same as the last few episodes of Nanaka. There's also one boy that they both care about that has different connections with them both 

Not that similar.. its just that Karada and Kotoura give me the same kind of feeling. Also its Both about girls that come to love the way they are. And a touch of Magic Of Course..! I think If you liked kotoura-san you will probably also like this ! 

I didn't think I'd find a link between Lamune and Koi Kaze, but here it stands. Asatte no Houkou shares the same silent authenticity that Koi Kaze possesses. This subtle communication by intimation, with characters who are at the same time simple and obscured. On the surface, a story about a girl who switches ages with a grown woman doesn't sound all that interesting, and it could go wrong in so many places . . . just like Koi Kaze could have gone wrong. But Asatte no Houkou has a similar level of craftsmanship as Koi Kaze, and that makes all the difference. 

Both feature an adult or near-adult that gets transformed into a small child if that is your cup of tea, and involve various pitfalls and struggles in trying to adapt to a smaller body, including hiding their identity in some parts and pretending to be a younger relative to themselves. The two series have this element in common but completely different tones. Detective Conan takes on a more action/mystery oriented atmosphere with many comedic highlights while Asatte no Houkou is relaxed and melancholic, mixing emotional drama with warm, happy moments 

Living for the Day After Tomorrow and Twin Spica are two slower-paced dramas with supernatural and slice of life elements peppered in. The main character is a young girl who is smaller than most her age and is kind to pretty much everybody, and is guided by an older character she meets at the start of the story. Much of either show is a bit of a character drama surrounding these two and some other characters around them, so expect some feels as you watch. 

Living for the Day After Tomorrow and Weathering With You are both about a pair of characters that meet unexpectedly during one magical summer. There's a bit of slice of life, supernatural, and familial drama with both anime, as well as good music and a pretty nice-looking visual presentation. The former is a slow-paced TV show while the latter is a very ambitious romance movie, though. 

Living for the Day After Tomorrow and Your Name are both about a pair of characters caught up in a supernatural, nearly magical, situation that changes their bodies and leaves them tied to each other. Watch the two will have to work together to deal with (and adjust to) their new situation along with pretty backgrounds and nice piano music. The former is more of a slow-paced character drama with slice of life elements while the latter is a far ambitious romance-comedy movie, though. 

Living for the Day After Tomorrow and Umi Monogatari are two relatively chill-feeling drama shows following two girls that meet during one magical summer. The two girls stay together, but one has some kind of familial drama while the other has relationship drama to their stories. These two shows are relatively slow-paced, but this should be fine if you're looking for something akin to iyashikei. Both have a very similar soundtrack, and if you enjoyed the music in one show, you're sure to like the other. 

Living for the Day After Tomorrow and Uta Kata are two slice of life dramas that follow two female characters during one particular summer in which magical/supernatural elements have been sprinkled in against their will. Their new situations bring them challenges in how to hide them from other characters and how to go about dealing with them. Expect a slow-paced character drama with nice backgrounds, good music, and some feels for either of these. 

It has an interesting story just like asatte no houkou. It also has really sweet romance. I don't know why but the overall feeling just reminds me of asatte no houkou. I think that anyone who likes one should like the other 

If I have to think about a series similar to this, the first link forms between Asatte no Houkou and Barakamon. I haven't watched that much from the slice of life genre, but these two both feature a warm relationship between a grown man and a little girl, and the pace of the story remains as warm and peaceful. Overall relaxing to watch, and makes one smile. 

Both are from the slice-of-life and drama genre. The younger main characters takes care of their older brother/sister and they gradually takes more notice of each others needs and feelings.  

Both series are about people who look far older/younger than they actually are. 

Fans of Asatte no Houkou's interpersonal drama might find much to like in Hitohira, and vice versa. The highlight of both shows are their strong characters and their growth over the series. Both could be said to be seinen anime who draw influence from shoujo sources, due to their character-driven plots. Also, Hitohira offers more lighthearted material than Asatte no Houkou does. 

YKK is not a romance like Asatte, but the place where the story desevolpes are kinda similar, and the painting style is very similar. 

Both of these shows focus on bittersweet slice of life type plots. Asatte no Houkou's plot is better developed, with more depth, than Sentimental Journey's though, because SJ is a series of short stories. Still, both convey a similar feeling and if you watched SJ for the slice of life setting and enjoyed the "almost but not quite romance" characters, then you might want to give Asatte no Houkou a try.  

The Anime involve the theme of dealing with the movement from childhood to adulthood along with what should and shouldn't be left behind. Of course, "Asatte no Houkou" delves into this theme using a supernatural element of a wish, but both series delve with the main characters and what they wish for their futures. 

Both anime are incredibly dramatic when they could be comedies. Not exactly to my taste, but if you enjoy one, then you will probably enjoy the other. 

Both are directed by Katsushi Sakurabi, this one is a director of character and development. Assate is, like Tsukihime, a slow anime. A series where little actions and silences are more important that the action. 

Both have a slow and reflective plot with supernatural events in both shows, and a slight melancholy tone. Both are about a Wish of one of the main characters. Both are about the value of family and friendship bonds.  

The similarities in these two shows stems from the similar settings and the slow pace that both stories use to tell the tales of the protagonists. A high school student in Natsume Yuujinchou and a middle school student and an adult in Asatte no Houkou. The narratives for both stories are slow and reflective, there are supernatural and mystical events in both shows, and the overall melancholy tone of both stories makes them comparable. Yuujinchou however is more episodic than Asatte, and the plot is superior to the lighter Asatte no Houkou. But if you liked one you'll probably like the other.  

This anime has the same sort of relaxed feel. The story is slow yet captivating and the romance like that of Lamune is gorgeous. I think fans of Lamune could easily enjoy this.