Contacting Your Winners
When an entrant signs into the Rafflecopter widget, whether it’s through Facebook connect or their email address, they’ll be giving you their name and email address. When a winner is chosen and you’ve decided to contact them, you’re recommended to get in touch with them through the email address they provided.
To make sure there are no discrepancies, make it clear in your promotion’s terms and conditions how you’ll be contacting winners. It also can’t hurt to include it on the landing page where your giveaway takes place.
When emailing your winners, shoot them a note that congratulates them, but more importantly describes the promotion that they won, what they won, and a link to where the giveaway was taking place. Give each winner a description of how they can submit their shipping information (if a prize needs to be mailed to them). Instead of asking them for their information in an email, shoot them a link to a survey or form that collects their information (creating a form through Google drive or Typeform works great).
Finally, link each winner to where you announced the giveaway’s winners, whether that’s a tweet or on Facebook. The giveaway feels more tangible to those that didn’t win if the winner comments or retweets the winner announcement -- your followers will see that actual people win your giveaways :)