This year, we are having postcards sent to each client with a picture of their pet from their Rover photo album. We made the postcards through a service and had them mailed directly to the clients. The cards were $0.90/card with postage included (we used Mailjoy).
We included a warm "Happy Holidays" note on the back with a recap of the amount of money we were able to donate to local shelters due to their support of our business. We donate 3% of profits to rotating shelters each month, and its been a big hit in years past to have this a part of our holiday greeting.
Front: Full size pic of dog/cat with the message:
"From our Family to Yours - Happy Holidays. Love, Me, My Husband, and our Dog"
Back: "We're incredibly thankful for the support we receive from clients like you and FIDO. Our time with them makes the whole year feel like the holidays. But we feel especially grateful in this season of giving that our clients' support has enabled us to make $XXXX worth of donations to local shelter pets this year. Our warmest wishes to you and yours this holiday season".