Not everyone in your list can get your marketing email. Unsubscribes, bounces, missing consent, unconfirmed signups and topic opt-outs all take contacts out before a send. What's left is your eligible audience: the only people a send or an experiment can reach.
This is part 2 of a three-part series. Part 1 built the list. This part explains who in it you may email, and part 3 keeps it that way.
The examples follow Retro Revival, a fictional vintage clothing shop, with made-up numbers.
In the list, then eligible
Every send applies the same rules, in the same order, to every contact. An experiment counts them before it draws a sample: its Audience & sample step shows In the list, then Eligible, then Targeted and In the experiment, with a Left out breakdown. Eligibility is checked again when the email actually goes out, so a contact who unsubscribes in between is still left out.
- In the list50,874
- Eligible46,320
Left out
- Unsubscribed or bounced · 2,870
- No marketing consent · 704
- Verified invalid address · 612
- Hasn't confirmed their subscription · 236
- Opted out of this email's topic · 98
- Missing or malformed address · 34
- Targeted6,420
Rock–Alternativeand1990s
- In the experiment4,000
- Arm A · 10% off · 2,000
- Arm B · Free shipping · 2,000
| Stage | Contacts |
|---|---|
| In the list | 50,874 |
| Eligible | 46,320 |
| Targeted | 6,420 |
| In the experiment | 4,000 |
| Left out: Unsubscribed or bounced | 2,870 |
| Left out: No marketing consent | 704 |
| Left out: Verified invalid address | 612 |
| Left out: Hasn't confirmed their subscription | 236 |
| Left out: Opted out of this email's topic | 98 |
| Left out: Missing or malformed address | 34 |
| Arm A · 10% off | 2,000 |
| Arm B · Free shipping | 2,000 |
Retro Revival has 50,874 contacts in its list. 4,554 of them are left out, so 46,320 are eligible:
| Left out | Contacts |
|---|---|
| Unsubscribed or bounced | 2,870 |
| No marketing consent | 704 |
| Verified invalid address | 612 |
| Hasn't confirmed their subscription | 236 |
| Opted out of this email's topic | 98 |
| Missing or malformed address | 34 |
Each contact counts once, under the first rule that applies. The sections below follow that order.
Missing or malformed address
The row has no address, or one that can't be an email address, such as "sam@" or a phone number in the email column. Fix the address in the list's grid and save.
Unsubscribed or bounced
These contacts are on your account's suppression list. An address gets there when:
- the person unsubscribes through the link in your email's footer;
- they report your email as spam, which counts as an unsubscribe;
- a message hard-bounces, because the mailbox doesn't exist;
- your sunset policy suppresses them after a long silence.
Suppression is account-wide. Someone who unsubscribes from one email isn't sent any other email from your account. The Contacts tab shows them with a bounced or unsubscribed badge. Resubscribe puts an address back, but use it only when the person asks: re-mailing someone who unsubscribed breaks their trust and anti-spam law.
Verified invalid address
Every address is checked when it enters a list. An address whose domain can't receive mail, or that bounced before, is marked invalid and never sent to, even if you kept it at import. A later check of the domain never clears a bounce.
No marketing consent
Every import asks How did these contacts agree to hear from you? Contacts imported as Purchased or prospect list never agreed to your marketing email, so no campaign, schedule, journey or experiment sends to them.
That answer sticks. Importing the same people again as "opted in" doesn't lift it. Only the contact can, by signing up through one of your signup forms. Contacts with no recorded answer, such as those added before the question existed or pushed in by an integration, are sent to as before.
Hasn't confirmed their subscription
With Require double opt-in turned on, a signup form saves a new subscriber as pending and mails them a confirmation. Until they click its link, every send skips them. Double opt-in costs a few signups, but each address that confirms belongs to a real person who wants your mail.
Opted out of this email's topic
Topics let people turn down one kind of email without unsubscribing from everything. Define them under Settings, in Preference center, such as "New arrivals" and "Sales". Then set the Mail topic on an email's Send page. Recipients see your topics on the page their unsubscribe link opens, and can untick one.
Topics are opt-out: a contact gets a topic's emails unless they untick it. This rule only applies to an email that has a topic. Retro Revival's reward email is filed under "Sales", so the 98 subscribers who opted out of sales emails are left out.
Already in another experiment
An experiment can also leave out contacts that another experiment still holds, with Leave out contacts who are already in another experiment (on by default). That keeps one test's offer from mixing into another's. Ordinary sends of an email that's under an experiment skip that experiment's contacts too, reported as "In an experiment on this email". Retro Revival ran no other test, so nobody was left out here.
Why this matters for a test
Eligibility is applied before targeting and sampling. Every contact an experiment draws is one it can actually mail, so both arms start from the same footing and their delivered counts reflect real bounces, not people you were never allowed to email.
It also tells you what your real list size is. Retro Revival's 46,320, not 50,874, is the number its targeting and its sample size planner start from.
Getting started
Open a draft experiment's Audience & sample step, or a send's audience, and read the Left out breakdown. A large "Unsubscribed or bounced" or "Verified invalid address" share is a sign the list needs cleaning: part 3 shows how. A large "No marketing consent" share means those contacts need to opt in before you can email them.