In advance, a one day pass was $15 + $1 service charge. This was the same total $16 that was charged on board on our last cruise.
A 7 day "length of cruise pass" was $99, a couples pass was $149. They also offered 3, 4, and 5 day passes. Multi-day and couples passes are sold only on board.
DO NOT believe the hype that "we only sell 30 of these." I've heard it on every cruise. And I've never had them refuse to take my money when I wanted to buy admission later (single day or fewer multi-days).
A single day could well have increased to $17 since our last cruise; $16 was the last price I experienced.