Hello
We are arriving into HND Terminal 3 and have a connecting flight from NRT after 12 hours. I am thinking of storing the bags somewhere in HND Terminal 3 (if available) and then go to Shibuya for a few hours and come back to HND and finally take the bus transfer to NRT. I did some research and can not find the correct information if there is a luggage storage facility at Terminal 3 at Haneda. Can someone who has recent experience storing bags at HND for 6-8 hours please advise on this. Thank you so much !

I, too, have a long layover at HND so have been looking for information. These are some of the websites I found that have information.

Coin Lockers (T3, levels 2 & 3: https://tokyo-haneda.com/en/service/...in_locker.html
Checkrooms: https://tokyo-haneda.com/en/service/...checkroom.html
Locations: https://www.jalabc.com/en/airport_co...terminal3.html
Photos of both checkroom & lockers: https://hktravelblog.com/japan/left-...aneda-airport/

I would be surprised if anyone here had such recent experience. Maybe you can find that at flyertalk. To me, it would be a matter of asking where it was, not if there was one.

The info was so easy to find am almost wondering if I understand the question:
Baggage Storage | List of Services | Service Guide | Haneda Airport Passenger Terminal (tokyo-haneda.com)

The ansswer is: 2F Arrival Lobby.(which is safe to assume but it is good that you are covering all the bases).

The question you didn't ask was: With a 12-hour connection can I ship bags from HND to NRT?
IDK the answer. It would be more expensive than storing, but the cost of baggage shipping in Japan is a really good deal. On some airlines it is possible to arrange baggage shipping before departure to Japan, but maybe not for same-day service.

The answer to my question may be no. I did find a Yamato location in/near Tokyo station that offers "Hands Free Service" including same day delivery from there to NRT.(you would find koin rokka at Tokyo station, Shinagawa, other stations)

There seems to be a location in the T3 departure lobby, too, and since they’ll be continuing to Narita, in case one is inside security, something to verify.

I’d also be checking for train station lockers, Shibuya Station or Tokyo Station.

The link I gave says the 3F departure lobby location in T3 is closed.

It may mean it isn’t open 24 hours and will open later. Some websites show real-time “open” & “closed.”

This is also an option I am thinking and found Shinagawa to be a good station.

How do you feel about the following itinerary ? Never been to Tokyo before, I need some expert advise to see if I should fit in all these or strike out some options from below.

6:45 AM arrive HND
8:30 AM drop off bags
9:00 AM train to senso ji
10:00 AM Reach Senso ji
11:00 AM train to Shibuya (Ginza line)
12:00 PM reach Shibuya
1:00 PM Train to HND to collect bags
2:05 PM Catch Shuttle from HND T2 3:25 PM arrive NRT
6:25 PM depart NRT

You can do your covid/immigration/customs stuff in advance via app or website.
That plan minimizes your baggage handling time at the cost of travel time. I think your time for Sensoji is too short and maybe add time in Shibuya to have lunch. You allow a ton of time at NRT.

Here is the yamato place that stores luggage and does same day shipping (from airports, maybe not tp airports, but maybe ship between aipiorts or same-day from HND to this location)
Tokyo Station Marunouchi North Exit Baggage Service Counter | Traveling to Japan | YAMATO TRANSPORT GLOBAL (global-yamato.com)

YEs I have done all the formalities on the Visit Japan Web app already, so hoping to get out of the immigration and customs ASAP and use that time