Train/ferry/bus scheduling

Oslo-Flam should be booked as a single journey on www.vy.no. The mainline train (Oslo-Myrdal) varies in price. Buying early will probably save you money. Those trains can sell out in advance, too, which is another reason to go ahead and buy those tickets if your itinerary is firm. (Understand the rules on cancellations and changes, though.)

Do not ever use Rail Ninja. You will be overcharged (probably significantly), and if something goes wrong, you'll probably run into confiscatory service fees to fix the problem. Google "Rail Ninja reviews" and you'll see what I mean.

Always try to buy rail tickets from the company running the trains. If you cannot get that to work because of credit card difficulties and PayPal is not an option, I'd suggest using www.thetrainline.com. It charges modest service fees and has a very good reputation. I'm not positive it displays all the options on each route, but on your route I don't think that will be an issue at all.

NorwaysBest sells tickets on the other ferry line (Fjord 1?). I believe Aurland is a request stop for those ferries. I'm not sure about Lustrabaatane. I hope another poster can help you on that point.

I just bought my Gudvangen-Voss bus ticket from the driver, but that was back in 2022, and more people are riding those buses now. It might be a good idea to buy the ticket ahead of time from www.skyss.no. Bus 950 is the one that originates right down near the dock. I believe Bus 450 picks up a short but uphill walk away. You can find the schedule on the Skyss website. I believe there are a few others on the schedule (through buses originating elsewhere). The current fare on Bus 450 seems to be Kr. 78; the othes might be different.

The train ticket from Voss to Bergen should be purchased from Vy. Those are local trains with no assigned seats, so they cannot sell out and the fare doesn't vary, so there's no rush. As far as I know, there's no reason you can't wait till you arrive in Voss and just buy the ticket from a vending machine--except that it would be a shame to miss a train departing for Bergen while you're doing that.

You can either book the Norway in a Nutshell through
FjordTours (easy peasy) or you can DIY the Nutshell yourself. You may save a few kroner doing it yourself, but it does take more work.

All of the trains should be booked with vy.no. Book your Oslo to Flåm journey as 1 trip via Myrdal. Be sure you select train, not bus, on the Myrdal to Flåm segment. Do not use Rail Ninja!

Note, that the Norwegian rail company does not accept most US credit cards (they lack required security features). You can use PayPal to purchase your tickets on the vy site.

There are 2 ferry companies between Flåm and Gudvangen. You want to book the quiet electric catamaran with Norways Best. You'll be able to select Aurland as your starting point.

The bus from Gudvangen to Voss is around 100nok per person, less for seniors. You can pay the driver with debit or credit card.

Again, use vy.no to book the train from Voss to Bergen.

My suggestion is to do a sample booking with FjordTours and follow the schedule they use to book your DIY Nutshell.

As regards the schedule for the Gudvangen to Voss bus you will find that on the Skyss journey planner- https://reise.skyss.no/en

it is a public bus which has about 4 dozen potential stops en route.

The senior discount applies for anyone aged over 67- https://www.skyss.no/en/tickets-and-prices/prices/senior-and-concessionary-discount/

If you pay on the bus it costs 78Kr, if you buy through Norway's Best they charge 200Kr for exactly the same bus.

There are also public buses from Flam to Aurland and at that time of year Norway's Best run their own bus, at a virtually hourly frequency- https://www.norwaysbest.com/en/flam/things-to-do/shuttlebus-flam-aurland

For the trains from Voss to Bergen the almost hourly commuter trains have a walk up fully flexible fixed fare of 278Kr. The infrequent long distance trains from Oslo have a non flexible ticket for 279Kr (fixed train, assigned seat) which must be booked ahead, a semi flexible non refundable ticket for 299Kr and a walk up, fully refundable ticket for 306Kr (assigned seat).

I recently booked the different legs of the NIN. I was a bit early (I try to plan well in advance!) and got on the VY site to book the train from Oslo to Flam. When I first booked, I could only get the Myrdal to Flam leg. This was confusing to me so I contacted the help email - [email protected]. The first part of the journey just hadn't been open up yet for bookings, and did shortly thereafter, at which time I booked and got a good seat but it was already relatively booked up! I was back and forth with the wonderful folks at [email protected]! They were helpful and supportive of my journey - even mentioned that I had gotten a good seat for the Oslo - Myrdal leg.
I looking ahead, depending on your travel dates, those first legs may not yet be open for sale. But keep looking as I believe the seats on the Oslo to Myrdal leg will sell out quickly. There are no seat assignments on the Myrdal to Flam (Flamsbana) portion.
I booked the Lustrabaatane Line as I wanted the older, more classic boat. I do not believe they stop in Aurland as the Fjords line does (www.visitflam.com).
The RS Norway book (and Scandinavia book) really helped me with this trip and provided details on each leg of the NIN!
Have fun! I will spend a night in Aurland, and two nights in Flam before departing on the Flam-Gudvangen cruise.