https://www.paypal.com/us/webapps/mpp/offers?view=details&offerId=LSMLJ46VGJA3N
Terms and Conditions
*Terms and Conditions:
“Eligible Participant”: Open only to residents of any one (1) of the fifty (50) United States or the District of Columbia who: (1) are eighteen (18) years of age or older; and (2) “are holders of a U.S. personal (including PayPal, PayPal Cash and PayPal Cash Plus premier or business PayPal account in good standing (“Valid Account”)” during the Offer Period (defined below)”; and (3) “receive an authorized email containing the invitation to participate in the offer (eligibility for/those who receive such an email will be determined solely by PayPal).”
“Eligible Purchase(s)”: Purchases made in USD using a Valid Account. Eligible Purchases do not include: (1) send/receive money transactions (including those marked as a “Goods and Services” payments), (2) charitable donations, (3) purchases made using PayPal.me; (4) PayPal Cash Mastercard®, PayPal Cashback Mastercard®, PayPal Prepaid Mastercard®, PayPal Extras Mastercard®, and PayPal Business Debit Mastercard® purchases made using the card directly and not through your Valid Account, (5) PayPal transaction fees.
“Offer Period”: Starts at 2:00 a.m. Pacific Time (“PT”) on December 19th, 2019 and ends at 11:59 p.m. Pacific Time (“PT”) on December 19th, 2019
“Reward”: $5 USD voucher that will be viewable in the “Offers” section of the Eligible Participant’s Valid Account for personal or premier accounts. For business accounts, the Reward will only be visible during checkout and on the purchase transaction receipt(s).
How to Qualify: Eligible participants must make an eligible purchase of $5 or more during the Offer Period. For certain offers as described in the invitation for the offer, Eligible Participants must activate the offer by following the steps in the invitation prior to qualifying.
How to Redeem: Once received, activated (where applicable), and qualified for, the Reward will be applied automatically to the Eligible Participant’s Eligible Purchase that qualified for the Reward. The Reward must be redeemed during the Offer Period and may only be redeemed as described in these terms & conditions. Use of the Reward will be reflected on the Eligible Participant’s PayPal receipt and/or in the transaction details of his/her Valid Account. Only 70,000 rewards are available for redemption; Rewards will no longer be available for redemption once this 70,000 maximum limit is reached. There is a limit of one (1) Reward per Valid Account.
Miscellaneous: Redemptions are final, will not be returned, and are subject to review and verification. The Reward has no cash value and cannot be redeemed for cash or transferred out of the Eligible Participant’s Valid Account, except in PayPal’s sole discretion. If item(s) purchased using a Reward are returned and the Offer Period has expired, PayPal will first refund the money spent to the payment method used to complete the Eligible Purchase and purchase amount in excess of the money spent (i.e., the value of the Reward) will not be refunded. If the Offer Period has not expired, the value of the Reward will be returned to the Offers section of the Valid Account and will be available for use by the account holder. PayPal may provide an alternate reward of equal value if it is unable for any reason to fulfill the Reward. PayPal reserves the right to cancel, suspend or modify this offer in part or in its entirety at any time without notice, for any reason in its sole discretion. Similar offers may run at the same time; qualification for this offer does not constitute qualification for any other offer. PayPal is not responsible and/or liable for any lost, stolen, late, incomplete, illegible, interrupted, delayed, or misdirected e-mail, Reward, or offer-related materials or correspondence or if any participant’s e-mail address, Valid Account, or other contact information does not work, is deleted, or is changed without participant giving prior written notice to PayPal. Offer is void where prohibited, if Eligible Purchases are not completed through legitimate channels, or if any offer-related materials are counterfeit, altered, defective, tampered with or irregular in any way. Certain offers may not be transferable. Any questions relating to the offer will be resolved in PayPal’s sole discretion and its decisions related to the offer will be final and binding."

I can add it to the $1,100 of stamps I already have from using my Office Depot rewards to buy stamps over the years. I have so many stamps that I keep them in my safe deposit box at the bank for safekeeping.