What does "auto-confirm new members" mean?
When you select "auto-confirm new members," all new subscribers that opt in to your site will be automatically confirmed onto your list. This is what's known as a "single opt-in" process.
Single opt-in means that subscribers do NOT need to confirm their subscription to be on your list.
If you left this box unchecked, subscribers would need to click the confirmation button in the Incentive Email before they were added to your list. This is what's known as a "double opt-in" process.
Double opt-in means they had to opt-in, and also confirm their interest before they are officially added to your list.
How should I decide which process to use?
In ConvertKit, you can use single opt-in AND double opt-in in tandem, since you change this setting on a per Form basis.
The advantage to single opt-in is you will grow your list more quickly. For whatever reason, some potential subscribers just don't click "Confirm," and thus you can never email them. If you use single opt-in, you won't have that problem.
Single opt-in is great for webinars or events, where subscribers may not be expecting to have to confirm, they just want to attend.
The advantage to double opt-in is your list will stay cleaner. You will have a more engaged, qualified list because they had to take the extra step and say "Yes, I want these emails!"
Double opt-in is great for delivering Incentive downloads, since they will have to click to download your Incentive anyway!
Is double opt-in required in my country?
Contrary to popular belief, a double opt in process is not explicitly required by law in any country, however it is strongly suggested by several countries, like Germany, which would require you to prove an opt-in in court, and a single opt-in is not proof enough.
Canada also recently passed CASL, which requires the same level of proof of opt-in in court.
And it's not just German or Canadian marketers that need to keep this in mind: the burden of proof is on the sender. If you have German or Canadian subscribers, you might consider using double opt-in to protect yourself.