Can I use a different passport for Japan?

I have 2 passports, and I will be making a multi-country trip with Japan as my second destination.

Nowadays I live in Country B almost all the time, so if anything were to happen to me or I need help/be air evacuated or so on, I would rather be treated as a citizen of Country B within Japan. My insurance is also in Country B. However, due to various reasons I am required to use passport A when entering or leaving the first destination.

So am I allowed to start my journey to the first destination using passport A, and use passport A for clearing immigration on arrival and departure to the first country, before switching to passport B on landing in Japan to clear Japanese immigration? I would then use passport B to leave japan, and then switch to passport A when I land back in the first destination. (I am going to the first destination before AND after Japan, with Japan sandwiched in the middle of the trip)

At the check-in counter in my first destination, before leaving for Japan, should I board the plane and show the airline the passport I will be leaving on (A) or the passport I will be using in Japan (B)?

You are permitted to use different passport if It is Legal.Dont worry.
As long as you stay in the right road, our creator is on your side.so Dont worry.

but, Japan and country B understand that you intend to hide your stay in the first destination country, if it is revealed.
for example, you buy illegal drugs in the first destination country and bring it to Japan to sell and return to the first (now the third) country to repeat it. (apparently no history of staying of the first destination country in passport B)

I don't understand the reason why your journey must be country B-the first destination country-Japan-the first destination country-(the final country B ?)
it can be done by country B - Japan- the first destination country - country B or country B - the first destination country -Japan- country B. those are more simple and understandable for everybody.

what you want to do is dazzling your positions un-traceably. it seems to be a classical cheap trick what everybody can come up with.

Ken, I can assure you I have no intention of doing any such illicit activities. The reason is actually quite simple. There are no direct flights between the place I am currently living and Japan, most of my family is in the first destination, and the first destination has direct flights to Japan. Therefore I can take a direct flight to the first destination, stay in the family home, and then take a direct flight to Japan from the first destination, with a family member who will be joining my trip from the first destination.
The dates for Japan are pretty much set, but I will be staying with family in the first (which is also the last) destination for several weeks after the Japan trip. When returning from Japan, I want to bring back sake, foodstuffs and other shopping for family back in the first destination. We will then spend some time together, then I head back to Country B.

As for the passports, Country B by law requires me to exit and enter on their passport, while the first destination would be easier with passport A. Furthermore, we are generally supposed to enter and leave a country with the passport with most ties to that country, and in the first destination all my registrations such as my bank account has passport A as my ID, set up when I was living in the first destination and long before I moved to Country B. But as I mentioned, while in Japan I would prefer to be using Country B's passport which would be consistent with my current health insurance, driver license etc, and I may be driving in Japan.

Lastly, not sure how much it matters but we are working healthcare workers with above-average income so hopefully they will see we do not want to have anything to do with drugs or any other shady activities that would jeopardize our professional registrations. I do not want to sound snobbish - that is not the intent, what I am trying to say is based on our occupations we are just not the kind who would risk our professional license if caught doing anything of that sort. Also the punishment for drug smuggling in the first destination is death, if someone wanted to smuggle drugs into Japan it would make more sense to go from Country B which does not have the death penalty.

You should show the immigration official the same passport to enter & depart the same country.

So enter & depart country 1 with passport A.
Enter & depart country 2 with passport B.

To the airline personnel, show them the passport you booked the ticket with.

>To the airline personnel, show them the passport you booked the ticket with.
I did not need a passport to book the tickets. The airline will need it at check in. So should I check in with the passport I intend to use for immigration on departure (B for leaving country B), or the one I intend to use when I get to my first destination (A for entering my first destination)?
I read that airline will add it to the manifest/passenger list, and usually customs more concerned about people coming in than going out, I may check in with the one I intend to use on each destination.
Only thing is the airline would then see 2 passports for the same booking - it is a multi-trip booking with the same airline as one booking.

One booking = one passport doesn't it?

The airline just checks if your name matches the reservation and you have the proper visa to enter the destination country. So it really doesn't matter which passport you show them.

Immigrations in Japan doesn't check your passport against the manifest. I have 2 passports with different names. The passport I show in Japan has a different name than on the manifest. They don't question me about it.

Are you not supposed to have 2 passports?

Just curious - why not make yr life simpler by just using one passport?

I know of ppl with 2 passports (or more) like you & I tell you, they sweat & stress themselves like mad each time they check in as they have to remember which passport to use.
And of course we�fve all seen movies of ppl with a briefcase full of passports- sorry can�ft help myself 🤩