Valve has added the ability to request refunds through the Steam interface, no questions asked.
There are some requirements before you can get your refund though
- You must request a refund within 14 days of purchase
- The game may not have been played for more than 2 hours
Refunds will be processed within a week of approval and credited to your Steam Wallet or back to the same payment method used at the time of purchase. There are some caveats to the refund destination based on payment method and country you reside in, you can read those scenarios here.
Some DLC won’t be available for refund however if it adjusts the main game in such a way that can not be reversed such as level cap increases. If the main game is played for two hours after purchasing DLC, a refund can not be requested event if the DLC content itself wasn’t used.
If you purchase a game as a gift, once the code is redeemed by the recipient you also can not request a refund regardless of whether the gift recipient played the game or not.
Comparatively, Origin offers refunds within 24 hours after you first launch the game, within seven days from your date of purchase, or within seven days from the game’s release date if you pre-ordered, whichever comes first. GoG.com will provide a refund within 30 days from purchase, but only if the game hasn’t been downloaded.