The promotions page lists all promotions created. This includes promotions active in current automation campaigns, promotions sent as part of an email blast, and any promotions that were created but not currently in use.
Each promo is displayed in the list with its validity date displayed underneath, for quick reference.
To the right, you can see how many people have redeemed each promotion to-date.
From this page you can also edit any promotion, including its settings (validity period, redemption limit) and design. Any changes you make to the promos will automatically update them in the campaigns they are active in.