Check your inboxes..
Mine was online only, some are reporting in store as well.
Title of Email: Up to $1,000 instantly! Reveal your Mystery Reward today.
Based on previous threads, it seems the reward amount is decided by first five digits of the code included in the email
Valid 10/5/17-10/14/17 on staples.com® purchases only. Mystery Reward is only available via this email and can only be redeemed by the original recipient of this email. Planned Offer Distribution: (3) $1,000 Mystery Rewards. (82) $500 Mystery Reward. (230) $250 Mystery Rewards. (389) $100 Mystery Rewards. (7,750) $50 Mystery Rewards. (45,800) $25 Mystery Rewards. (139,491) $10 Mystery Rewards. Approximately (581,200) $5 Mystery Rewards. Rewards are not redeemable for cash. Staples is not liable for unclaimed or expired rewards. Staples Rewards® cannot be redeemed for or applied against cash, taxes, credit remittance, shipping charges, custom printing orders placed online, promotional products, any purchases made on print.staples.com, staplescopycenter.com, staplespromotionalproducts.com, staplescustomprint.btobsource.com, appcenter.staples.com, gift cards, prepaid phone cards, postage stamps, prior purchases, Staples Industrial(sm) purchases, purchases made on staplesmobile.com, or purchases on third-party websites. Purchases eligible for rewards is the amount paid at checkout after application of all promotions, coupons and rewards redemptions. To the extent that Product specific coupons were applied pro rata in a transaction in the past for the purposes of calculating Qualifying Purchase Amount(s) for Rewards, this means such coupons were proportionately allocated across all items purchased in a given transaction. Purchases made pursuant to a contract with Staples Contract & Commercial, Inc., are not eligible for the Staples Rewards Program. The sale, barter or transfer of rewards, except by Staples, is expressly prohibited. Abuse of the Staples Rewards program, including violation of program policies, or other improper conduct as determined by Staples, may result in legal action, cancellation of member's account, exclusion from the program, forfeiture of all rewards accrued, and liability for past rewards redeemed. Expired rewards cannot be reissued. Staples reserves the right to change the rewards program at any time without notice.
Mine was $25.00 fwiw.