Skip the tourist 'Welcome Card' math — Here's the real breakdown. Current BVG prices: single tickets €3.50 (zones AB) or €4.40 (ABC including airports), day passes €8.80 (AB) or €10 (ABC). You need exactly 3 trips to break even on day passes.

Typical tourist pattern: airport arrival (zone C), 2-3 city exploration trips (zone AB), airport departure (zone C) = 4-5 total journeys. ABC day pass wins every time. Week passes (€36 ABC) only worthwhile for 4+ day stays with heavy transit use.

Pro backpacker hack: Day passes valid until 3am following day — Buy after 10am to maximize value. Kids under 6 ride free (no ticket needed), ages 6-14 pay reduced fares. Passes cover S-Bahn, U-Bahn, trams, buses, plus regional trains to Potsdam.

When singles make sense: staying central Mitte, walking most places, using transit 1-2 times daily max. Otherwise ABC day passes represent one of Europe's better public transport values compared to individual tickets.