It's like EVE. You can pay a monthly subscription of $15 per month ($14 with 3 month plan, $13 with 6, $11 with yearly) or you can buy C.R.E.D.D. off the player's market with in game currency and use it to pay for a month of time. However that means another player would have to first buy CREDD for $20 from the online store and then sell it on the player's market.
It's daring since the most recent MMOs that came out in the west with subscriptions haven't lasted too long before they switched to F2P. Wildstar is only F2P if you can earn enough every month to buy a CREED off the player market.