Pls explain how does the Swiss half fare card and Bernese oberland pass work together?

You get a discount on the Berner Oberland Pass with the Half Fare Card. The Berner Oberland Pass coverage changed this year and is no longer as useful in the Grindelwald area, Take a look at the Jungfrau Travel Pass instead. That also has a discount with the Half Fare Card. https://www.jungfrau.ch/en-gb/jungfrau-travel-pass/

PS. WengenK gave you very good advice on your other post.

The Half Fare Card is a set price (130 CHF?). If you ONLY buy that pass, you get discounted tickets on eligible trips (train, boat, gondola). The pass is good for a month and valid throughout Switzerland.

If you buy the HFC and buy the BO Pass or Jungfrau Pass, your BO or Jungfrau pass will be discounted. These passes have a limited area of validity. You’ll need to read the details of each to see which suits your plans best.

In prior years, the BO Pass was great because it covered almost all travel in the region 100%. With the pass, you didn’t have to buy tickets each time. You just hop on a train/boat/gondola. The coverage has changed recently, making it less convenient since ticket are only discounted so you have to purchase them before boarding.

From my reading of the latest BO pass info - the transit lines that say ‘free travel’ do not require a ticket to be purchased. So my assumption is you can get on and off with only the pass as before.

So my assumption is you can get on and off with only the pass as
before.

Only for routes covered 100% with the Pass.

As stated above, many of the routes previously covered at 100% are now only covered 50% or 25% with the BO Pass. For those routes, one will need to purchase tickets.

https://www.berneseoberlandpass.ch/news-2025/

Yes exactly - and those lines on the BO web site are clearly marked ‘free travel’
https://www.berneseoberlandpass.ch/public-transport/?gad_source=1&gbraid=0AAAAADKUliyB3E3BwNG1ZcefCdF1cRNNt&gclid=CjwKCAjwvr--BhB5EiwAd5YbXn9H2DXPRzxTNXIcgVJ2Iuk8WxojqlcMzfWooM1E4b0Ny79gxZSdxxoCDdYQAvD_BwE
I just wanted to note that those should still be hop on and hop off (unless I was reading wrong). Maybe not for OP’s intended area of hiking but for many lines of transit for hiking still free.

mggtravel, yes, for anything marked “free travel” with the Pass, the Pass acts as your ticket. No need to purchase anything. Sorry if I misunderstood.