Procedure for entering Japan

I live in Japan, so this question isn't regarding me, but others. Is there any written procedure for entering Japan from a foreign country? I've heard so much conflicting information from the internet as well as firsthand experiences from both Japanese and non-Japanese travelers. My questions are as follows...

- Do you go through customs first and then go to quarantine area to be tested for COVID?

- Is the test immediate?
If not, are people expected to wait in the quarantine area of the airport until results?
Is it hours or days?

- If the test is positive, are people forced back onto a return flight?
Even though this means infecting others?

- If the test is negative, are people still required to quarantine for two weeks?
If yes, where? My friend's family were denied a hotel stay despite providing negative results.
My friend had to drive 5+ hours to pick them up because she wasn't anticipating the hotel denying them.

The situation is currently rapidly changing in regard to tests and quarantine in recent weeks.

As you know, no foreigner is currently allowed to enter Japan besides residents of Japan and business travelers from a small number of countries. New visas are not being issued for the time being. This situation is going to continue at least through January, but may get extended.

- Do you go through customs first and then go to quarantine area to be tested for COVID?

I believe the order is quarantine -> immigration -> customs

- Is the test immediate?
If not, are people expected to wait in the quarantine area of the airport until results?
Is it hours or days?

Yes, typically 2-6 hours.

- If the test is positive, are people forced back onto a return flight?

I believe they are being sent to a hospital or hotel designated for infected people.

- If the test is negative, are people still required to quarantine for two weeks?

Yes, at the moment, everybody is again required to do the 2 week quarantine. There were some exceptions previously, but these exceptions were suspended until at least January 31.

Hello Uji! Thank you so much for the information! Everything changes so fast lately, it�fs hard to keep up to date!

None of my family or friends have any intention of visiting any time soon, but it got me curious since 2 out of 3 immediate family members in the US have received the vaccine! I�fm wondering if that will change things too!

It has been the same procedure for months (six months or more) - essentially what Uji described is what happened for a friend of mine in July - not much has changed once they got some early bugs removed from the system.
As for information - always go to official sites (preferably in Japanese) rather than places like blogs or forums.

Vaccinations currently have no impact on the entry procedure into Japan, but this may change a few months down the road, as well. You can expect the details of the entry procedure to change constantly during the entire year.

"My friend's family were denied a hotel stay despite providing negative results.
My friend had to drive 5+ hours to pick them up because she wasn't anticipating the hotel denying them."

I am not surprised, if it happened. the hotel has no duty to take a risk. only the sponsor, who invited foreigners, takes ALL responsibilities about them. eventually, I think it is sponsor's responsibility to find the accommodations. therefore, it was your friend's fault caused by optimistic misunderstanding.

I have heard that travelers from the USA who are family of Japanese residents can visit Japan on a visa. Does anyone know if it is possible to visit a close friend on the visa? It seems the visa is listed as "to visit family or acquaintances" on their website but I don't know if only family is being approved right now.

No, you can't. your visiting is not essential.

I was under the impression that Japan had again banned entry to foreigners, and only those with citizenship or residency could enter, regardless of family ties.

https://www3.nhk.or.jp/nhkworld/en/news/20201227_02/

I would follow the line of the poster above - if your travel is not essential, assume you won't be allowed in. Any entry to see family, etc. would be for personal reasons - perhaps a family member is dying, or has died, or is very sick. But heading over for travel, or visiting friends, isn't classed as "essential".