Spotify is offering a couple of holiday deals and they're not limited to new users like these sorts of discounts typically are. First time Spotify Premium users in the US can get three months for $0.99 as long as they haven't used a 30-day trial before or provided credit card information in the past. And any Spotify Premium user that cancelled their account prior to October 16th of this year can get three months for the price of one ($10).
Spotify says similar discounts are being offered in the majority of its markets globally, though some regions' deals may have slight differences. They're available through December 31st and you can see the terms for each here and here.