Bern to Wengen by train

Interlaken is where the network of mountain railways in the Bernese-Oberland connects with SBB's national rail network.
You will have around 8 mins to make the connection into the train on to Lauterbrunnen at Interlaken Ost station, but the connection is virtually guaranteed, in terms of the arrival and departure times of the trains.
So you can be sure of making this connection, if you book tickets that are valid for the end-to-end journey.

Eight minutes may not be enough time to buy a ticket for the journey on to Wengen (via Lauterbrunnen) from the ticket desks at Interlaken Ost station.
Though if you will be travelling with any type of rail pass, including Swiss Day Passes, you'll need to go into the ticket office, to buy a discounted ticket for the journey on from Lauterbrunnen to Wengen.

Then the connection at Lauterbrunen into the train on Wengen is a simple as can be.

Booking Tickets:

Tickets can be purchased online for end-to-end journeys which involve taking a SBB train + the BernerOberlandBahn train on to Lauterbrunnen + the WAB train on to Wengen

‘Individual tickets’ can be used on any train(s) on your travel date, but they tend to be comparatively expensive.

'Supersaver' tickets are cheaper, as the portion of the journey by the SBB train can be discounted by up to 50%, but these tickets are train departure specific.
So if you book a Supersaver ticket and a flight delay etc, causes you to miss a train you are booked on to, you will have to book another full-price ‘Individual Ticket(s).
You can then apply for a refund of the Supersaver ticket, but the application costs CHF 10.

Hence it’s worth comparing the ticket price of a journey with the price(s) e of Saver Day Passes (see below) they might save you money and can also allow for a less stressful journey.

Using Saver Day Passes:

Now that the Swiss Transfer tickets have been discontinued a Saver Day Pass may save you money, if you can book at least a couple of weeks ahead (usually), so that you can obtain the pass at a discounted price.

They can be cheaper than tickets for the end-to-end journey, though they are more likely to be a money saver if you will be making a day return trip.
But this journey to Wengen can be an exception.

That's because Saver Day Passes can be used for free travel on the trains between Basel and Lauterbrunnen, but unless they have purchased with a Half-Fare card , they can't be used for the part of the journey between Lauterbrunen and Wengen
So tickets for the final section of the journey will need to be booked prior to boarding the trains, in the ticket offices at Interlaken Ost or Lauterbrunnen stations.

Additional Information:

More general info is available on our GUIDE to taking the train to Swiss Ski Resorts.