The order will see Supernatural return for a ninth year, while Vampire Diaries will be back for a fifth season.
Freshman drama Arrow - starring Stephen Amell - will also be back for a second run.
"We said last year that one of our goals was to establish building blocks to grow on, and now with our new hit Arrow and fan favourite Supernatural on Wednesday night, and the continued success of The Vampire Diaries on Thursday, we've been able to do that," said The CW's president Mark Pedowitz.
"Not only do Arrow, Supernatural and The Vampire Diaries perform well on-air, they're also extremely successful for us both digitally and socially. I'm thrilled to have all three shows returning to our schedule next season."
Arrow was widely expected to get a second season after attracting ratings of up to 4.1m.
Pedowitz also announced last month that Supernatural had a "good shot" at being picked up for a ninth season, while Vampire Diaries exec Julie Plec recently claimed that her show could last for ten seasons.
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Watch a promo for Arrow below: