Upvote:2
The point of the 'sufficient funds' test is to see if you will risk getting into financial strife during your time in the country. Many countries test this, and there's no hard or fast rule for how much cash you'll need.
When considering your access to funds, the officer will take a number of factors into account:
They'll then weigh those into consideration, or possibly ask you more questions about your activities. They don't want tourists needing bailing out, basically.
So we can't really answer a specific $$$ figure. But if you're confident you won't need more than that money to cover yourself, and can show you've done the calculations and can explain that to an officer, you are unlikely to have any problems. There's a good chance they won't even ask if you're basically just transiting through.
Upvote:2
I've been to Japan many times and have never been asked anything like this. In any case, in the extremely rare chance that they do say something, a copy of your flight itinerary (which shows you're leaving Japan the next morning) and your 20,000 Yen should be totally fine. Where are you staying? If you are staying with a friend, make sure you know their address. If not, have you pre-booked a hotel? If so, bring confirmation of that. But still I would be shocked if they asked you anything about it.
I would not worry about this at all.
That said, you don't have a credit card or an ATM card, and you're going on (what sounds like) a reasonably long trip? What are you doing for money on the rest of the trip?
Upvote:5
¥20,000 cash, plus a credit card, is lots for an overnight and a transit to Narita (I live in Tokyo). Where you are from and what you look like is usually a much bigger factor with Japanese immigration than how much cash you have - in 15 years of travel they have yet to ask me a single question at immigration.
FYI, you won't be able to do much in Tokyo. Arrival at your Tokyo hotel will be 9-10pm depending on where, you will need to be at Narita by 3:30 and it takes 2 hours to get there. Published times of 55 minutes are platform-to-platform times of a limited express train that runs twice an hour. Find station, buy ticket, find platform etc. etc.