Star Wars: The Old Republic is going free to play "later this fall." As you might expect, there will be considerable restrictions placed on players enjoying the free version. Good news: all story missions for all classes will be free. Less good news: if you want to run more than three PvP warzone sessions a week, gain rewards for more than three flashpoints per week, have more than one crew skill or revive more than five times in the field, you'll have to buy Cartel Coins. These can be spent on weekly passes to remove flashpoint and Operation restrictions, or you can blow them on new gear customisation options.
If you've subscribed to TOR at any point, you'll already have some Cartel Coins to your name. You can check how rich you are by logging into the Cartel Coin Ledger page with your TOR account. To claim them you'll need game time in your account (via a game time card or ongoing subscription). If you continue to pay a monthly subscription fee, you'll get unlimited access to all of TOR's features, and a monthly dividend of Cartel Coins to spend on whatsoever you wish.
Once you've made a single purchase, your account will be upgraded to "preferred" status, which will grant players extra bank slots and decrease restrictions to chat and trade functions. The Sprint ability that lets your character run faster will unlock at level 15 for free to play players.
If you don't pay you won't be able to run Operations (TOR's equivalent of raids), you won't gain rewards past the first three Flashpoints (TOR's dungeons) you play per week. You'll be limited to three Warzone PvP scraps per week and three space missions per week. You'll also have to contend with a longer cooldown on quick travel, which can be lifted with a one-shot authorisation purchase. You won't be able to equip powerful purple items without first buying a license with Cartel currency.
You can browse the full list of restrictions on the Star Wars: The Old Republic site . For more on Cartel Coins, check out the free to play FAQ . There doesn't seem to be a way to earn Cartel Coins without paying for them, which means you'll almost certainly have to put down some money on the journey to level 50, unless you're okay with moving slower than everyone else.
Update: EA have sent word to confirm that the Sprint ability will be available at level 15 in TOR's F2P option. The article has been amended to reflect that.