Lauterbrunnen Trip / Railway pass questions

From my understanding the regular Swiss Pass is good for cable cars up to Murren and 50% off after that. Can anyone confirm that?

Yes, that is correct.

It should not take very long to purchase a Swiss Travel Pass at Zurich Airport train station. I just think you might spend a bit of time calculating the cost. The Swiss Travel Pass is a very expensive product. Convenience wise, it can't be beat, since once it is validated, you just jump on the next train going in that direction. But take a little time to see if the Half Fare Card will save more money. You will need to buy a train ticket for every journey, but you get the ticket at half price.

Check out the pdf "Map of Validity" on the right hand side of this page. http://www.sbb.ch/en/leisure-holidays/holidays--short-breaks-in-switzerland/swisstravelsystem/swiss-travel-pass.html

Use the website to estimate train ticket costs. Just remember that the first cost shown is the half-fare cost. That is why it says "from CHF XX.XX". Even the Swiss aren't averse to a little bait-and-switch.

Sam, I must take issue with you when you say "cost shown is the half-fare cost. .... Even the Swiss aren't averse to a little bait-and-switch".
First, over 50% of SBB's passengers have a half-fare card or another type of season ticket. I have read this in more than one place. Therefore this is the correct fare for the majority of travellers.
Second, they are not trying to mislead you into buying from them instead of a competitor. With very few exceptions there is only one operator for a particular route, and all operators (including buses and city trams) recognise the half fare card. This is not like rival side-by-side supermarkets, it is not "bait and switch".

Heidi, also consider the Berner Oberland pass. This is only valid once you get to the Berner Oberland, so you will have to buy full fare tickets from and back to Zürich Airport, but it gives better discounts and better coverage of the mountain railways in the Berner Oberland.
Details are here: http://www.regiopass-berneroberland.ch
The map showing the area covered is here: http://www.regiopass-berneroberland.ch/assets/PDF/BLS-RAIL-Regio-BE-XL-16WEB.pdf

All Swiss Passes and Half-Fare Cards that you buy ahead are now pre-validated for a specified travel period, so that's not a good fit with flying standby. It's lucky that Switzerland is one country that does sell passes there in train stations. Since station staff no longer have to validate passes for everyone, it may make the line to buy a pass slightly shorter.

@ Chris,

When I look up a ticket, say Zurich Airport to Lauterbrunnen, I get a table of solutions, each one marked "from CHF 40.30" When I click on the "Fare/Buy" button, and I mark "no reduction" (don't have a Half-fare card), the actual purchase price comes up as 80.60 CHF.

I am surprise only 50% of Swiss residents have half fare cards, I would have guessed closer to 100%.
But it is something that must be accounted for when doing price estimates.

It doesnt seem as if I can buy the berner oberland pass online - just the swiss pass. Can anyone confirm that? Also after our trip to lauterbrunnen/murren we might be heading on an overnight train from Zurich. Does the Swiss pass work for international destinations?

Swiss Pass validity stops at the Swiss Border.

You can buy the regional Berner Oberland Pass online if the train stations listed are not convenient: http://www.regiopass-berneroberland.ch/offer-2016-april-23-to-october-31/.

Heidi, it is easier to buy the passes when you arrive in Switzerland. Takes but a minute.