Explaining contact opt-in types

Explaining contact opt-in types


Every contact in any of your address books has an 'opt-in type'. 

This lets you know how the contact opted in to being emailed by you.

The opt-in type is displayed when listing contacts in an address book, plus it can be manually changed when editing a contact.

There are four opt-in types that a contact can have assigned to them - 'unknown', 'single', 'double' and 'verified double':

  • Unknown - this contact is in your account, but you've not told us how they opted in
  • Single - this contact has opted in via a signup form, or you've told us they've done the equivalent
  • Double - this contact has opted in, and you've stated that they've confirmed their subscription
  • Verified double - this contact has opted in, and confirmed their subscription via an email sent by us

Significance of opt-in types

Opt-in types give you an indication as to how engaged your contacts are likely to be. If a contact has a 'verified double' status, for instance, then the likelihood is that they're truly interested in hearing from you, as they've taken the time to not only sign up but also open the verification email and click the link.

'Verified double' also gives you reassurance. Verifiable double opt-in is best practice for adding contacts to your address books, guarding you against unfair spam complaints as you'll have a record of it.

Manually changing an opt-in type

When editing a contact, their opt-in type can also be manually changed and saved. For instance, you might want to do this if the opt-in type is originally 'unknown' but you then subsequently agree opt-in confirmation with the contact outside of an opt-in process using a registration/signup form, etc.

However, you can't manually change a contact's opt-in type to 'Verified double'; this is only automatically changed once confirmation comes from the contact clicking the link in the verification email. You can't manually change a contact's opt-in type once it has become 'Verified double' either.

More on the different opt-in types


This status is assigned automatically by the system to contacts who don't have an opt-in type set when they're manually bulk imported or individually added to your address books (i.e. contacts who haven't joined via one of our signup forms).

'Unknown' is fine if you know for sure you've acquired the contact safely and legally. However, you need to be wary with this status type, as 'unknown' says just what it means; the system does not know the opt-in type of the contact, which may mean you don't fully know how such contacts have been sourced and whether they've willingly opted into your communications or not. Our data Watchdog does its best to check lists are clean in terms of problematic data - but ultimately it is your responsibility to make sure you're sending to contacts interested in receiving your email.

The bottom line is that if you don't know whether a contact has opted in or not, then we wouldn't recommend sending email to them. If you do send unsolicited email, you will be exposing yourself to possible complaints to anti-spam authorities which could result in you being blacklisted. This harms your, and our, reputation and deliverability rates.


This status means a contact has signed up to receive emails via one of our signup forms.

However, there is still a drawback to this. It means people could sign up on behalf of friends, family and other acquaintances, as long as enough details are known about them. Although unfortunate and unfair, this could possibly result, again, in unsolicited emails being sent to such contacts and complaints to anti-spam authorities being made about you. It is certainly something to be wary and mindful of.


Double opt-in means not only has someone signed up to receive your email but you have also then sent a confirmation email containing a verification link for them to click. By clicking this, the recipient confirms the email address really does belong to them, at which point they will be able to receive communications. This is widely regarded as the most effective way to ensure you're observing best email marketing practice.

In terms of the system, setting a contact's opt-in type to 'double' indicates that they have gone through this process, albeit on a separate system to ours. This is useful, for example, if you are importing contacts who have double opted-in from another system that you had previously been using.

We leave this up to you to apply, and in all cases we rely upon your honesty in using it; otherwise it is your and our reputation and deliverability rates that will be adversely affected. 

Remember - if a contact complains and contests their double opt-in status, then you will need to have a record of it yourself. We won't have a record because it wasn't done via our platform.

Verified double

This is just as above, but with the key difference being that we can completely verify it because the double opt-in has been performed using our system. The contact will have joined your address book via one of our signup forms and will have verified this by clicking on the link in the triggered email that's then sent to them.

For details on setting this up, read Using 'double opt-in'

If the double opt-in confirmation email has been sent but the verification link has yet to be clicked, this will be indicated when you go to edit a contact, next to 'Status' where it will say 'Pending optin'.

You can set up double opt-in for subscribers using a signup form, as well as setting it as a requirement for contacts already in your address books. Doing this will automatically send a double opt-in request to the contact, whilst immediately removing them from any address books until the contact clicks the verification link.

If a contact complains or queries their subscription and opt-in type, the 'Edit contact' page also stores their last subscribe date as well as their opt-in type, all of which can be useful to establish the facts.

We strongly recommend using double opt-in verification if you want to ensure you're properly observing what is considered to be the minimum in email marketing best practice.

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