The break-even maths
Every ticket costs half, so the card amortises at CHF 380 of full-fare travel per year. Two return trips Zurich–Geneva already get you most of the way. If you commute with a route pass, the Halbtax still halves everything OUTSIDE that route.
Halbtax vs. GA
The GA suits heavy daily travellers; the Halbtax suits everyone else – occasional commuters, weekend travellers, families (children's co-cards are cheap). Most Swiss adults hold one; treat it as the default and prove you DON'T need it.
Track one month of trips
Log your real transport spending for a month – the Halbtax/GA/route-pass decision usually makes itself.
Track these costs in your own budget: create your free Swiss budget in BudgetHub – in English, with Swiss categories built in.