Brevo inbox placement testing measures where a real test email lands after Brevo sends it. MailSlurp supplies controlled Gmail, Google Workspace, Outlook, and Microsoft 365 seed addresses, matches the message using a unique marker, and reports the observed inbox, tab, spam, or not-received outcome.

This is more specific than treating a Brevo spam check or successful delivery event as proof of inbox placement. Content and authentication checks identify risks; the provider seed result records what happened to the marked message during the test.

## Quick answer

To test Brevo inbox placement and spam signals:

1. Create a new MailSlurp inbox placement run.
2. Copy the unique marker and all four current provider seed addresses.
3. Add the seed addresses as contacts in Brevo.
4. Open **Settings > Campaigns > Test List**, add all four seeds, and save.
5. Add the exact MailSlurp marker to the Brevo subject or message body.
6. Open **Preview & test > Send test email**.
7. Select all four current seed recipients and click **Send Test**.
8. Return to MailSlurp and choose **Get your score**.
9. Review every provider row, then inspect **Content issues** and **Domain issues**.

Create a fresh MailSlurp run for every campaign revision. Its marker and seed addresses identify one specific test.



{{LANDING_SHORTCODE:POST_CTA_BANNER:%7B%22title%22%3A%22Measure%20Brevo%20campaign%20placement%20before%20launch%22%2C%22content%22%3A%22Send%20the%20final%20Brevo%20campaign%20to%20controlled%20provider%20seeds%2C%20then%20compare%20placement%20and%20campaign%20health%20signals%20in%20one%20result.%22%2C%22buttonHref%22%3A%22https%3A%2F%2Fapp.mailslurp.com%2Fobserve%2Finbox-placement%22%2C%22buttonText%22%3A%22Start%20an%20inbox%20placement%20test%22%2C%22buttonTheme%22%3A%22blue%22%2C%22image%22%3A%22%2Fassets%2Fhome%2Finbox-placement-ui.png%22%2C%22imageAlt%22%3A%22Email%20deliverability%20and%20inbox%20placement%20results%22%2C%22imageWidth%22%3A%22800%22%2C%22imageHeight%22%3A%22548%22%2C%22imagePosition%22%3A%22%22%7D}}



## Before you begin

Prepare the Brevo email you intend to test. Confirm the sender identity, sending domain, subject, preview text, links, hosted images, footer, subscription settings, and unsubscribe behavior match the planned campaign.

Brevo requires each Test List address to exist as a contact. Its documented Test List limit is 20 addresses, so the four current MailSlurp seeds fit alongside a small internal QA group. Do not use customer addresses for this controlled test.

## Step 1: Create a MailSlurp placement run

Open **Deliverability**, choose **Inbox placement**, and create a new test. Copy the unique marker and all four provider seed addresses.

![MailSlurp inbox placement setup with arrows showing the unique marker and four provider seed addresses](/assets/guides/brevo-inbox-placement-testing/01-mailslurp-seed-run.webp)

The seed set covers personal and business mailbox experiences across Gmail, Google Workspace, Outlook, and Microsoft 365. Use the values displayed by the active run rather than addresses from an earlier test or screenshot.

## Step 2: Add the current seeds to Brevo

Add the four MailSlurp seed addresses as Brevo contacts. Then open the account menu, choose **Settings**, open **Campaigns**, and manage the **Test List**.

Enter one seed address per line and save the list. Remove expired seeds from earlier runs so the recipient selector is unambiguous. If the new addresses do not appear immediately in the campaign, refresh the Brevo page.

For a larger or repeatable production-like workflow, MailSlurp's provider CSV can be imported into a dedicated Brevo contact list. For the direct campaign QA workflow shown here, the Test List keeps the send controlled and fast.

## Step 3: Keep the marker in the campaign

Add the exact MailSlurp marker to the Brevo email subject or body. A clear test subject is:

```text
Brevo inbox placement test mip-example123
```

Brevo adds `TEST -` to the subject of test sends. That prefix is expected; keep the MailSlurp marker unchanged elsewhere in the subject or body so the run can match the message.

## Step 4: Select all four seeds and send

Open **Preview & test**, choose **Send test email**, and select all four seed recipients from the Brevo Test List. The selector may display the first address plus a count such as `+3`; verify that the count represents all four seeds before sending.

![Brevo Preview and test dialog with arrows showing the placement marker, all four selected seeds, and Send Test action](/assets/guides/brevo-inbox-placement-testing/02-brevo-marker-and-seeds.webp)

Click **Send Test** once. This sends the same marked campaign copy to the four controlled provider addresses.

## Step 5: Get the inbox placement score

Return to the active MailSlurp run and choose **Get your score**. Results update as each provider receives and classifies the message.

![MailSlurp Brevo inbox placement result with arrows showing the delivery status, provider rows, and issue tabs](/assets/guides/brevo-inbox-placement-testing/03-mailslurp-placement-results.webp)

Do not replace a slow or missing result with an assumption. Keep the run open until the observation window resolves each target.

## Step 6: Interpret provider placement

| Result           | What it means                                                                              |
| ---------------- | ------------------------------------------------------------------------------------------ |
| Primary or inbox | The message reached the provider's main inbox experience                                   |
| Promotions       | The provider delivered the message to a promotional category rather than the primary view |
| Focused or Other | The provider delivered the message to a named tab or filtered inbox experience             |
| Spam or junk     | The provider classified the message as unwanted or suspicious                              |
| Not received     | MailSlurp did not observe the message at that seed during the test window                  |
| Pending          | The provider result is still being checked                                                 |

A promotional or filtered-tab result is delivered, but it is different from primary placement. Judge the outcome against the purpose of the message.

## Step 7: Review content and domain issues

Open **Content issues** for message-level findings and **Domain issues** for sender and sending-domain checks. Use the result to choose a specific correction:

- verify SPF, DKIM, and DMARC alignment for the Brevo sending domain
- confirm the visible From address and reply handling
- replace broken, redirected, or unnecessary links
- keep text, images, and alternative text balanced
- preserve a clear unsubscribe and preference path
- avoid sudden volume changes or unengaged customer audiences
- retest the complete revised Brevo email with a fresh run

Change one meaningful variable at a time when comparing results.

## Brevo inbox placement checklist

Before treating a run as valid, confirm:

- the marker and seed addresses came from the active MailSlurp run
- all four seeds exist as Brevo contacts
- the Brevo Test List contains all four current seeds
- old seed addresses and customer addresses were removed
- the marker appears unchanged in the subject or body
- the final sender, sending domain, content, and links were used
- the recipient selector shows the first seed plus three additional recipients
- Brevo reported a successful test send
- all MailSlurp provider rows belong to the current run
- content and domain issue tabs were reviewed before retesting

## Troubleshooting Brevo placement tests

### The seeds do not appear in the campaign

Confirm each address exists as a Brevo contact and is included in **Settings > Campaigns > Test List**. Save, refresh the campaign page, and reopen the recipient selector.

### MailSlurp does not recognize the Brevo email

Confirm the exact active marker appears in the delivered subject or body. The `TEST -` prefix is safe, but the marker itself must not be changed or truncated.

### Fewer than four results arrive

Compare the Brevo Test List with the active MailSlurp seed set. Reopen the recipient selector and verify the first selected address is followed by `+3`. Then wait for the complete observation window.

### A provider stays pending

Keep the result page open while MailSlurp checks the provider. A delayed or not-received target is evidence from the test and should not be replaced with an assumed placement.

### A content score looks good but placement is poor

Content checks do not reproduce every provider's filtering, reputation, engagement, and historical signals. Review the provider rows, authentication, list quality, sending pattern, and content together.

## FAQ

### How do I test Brevo inbox placement?

Create a MailSlurp placement run, add its four current seeds to the Brevo Test List, keep the unique marker in the campaign, send one Brevo test to all four recipients, and review the provider rows.

### Is Brevo deliverability the same as inbox placement?

Delivery indicates that the receiving system accepted the email. Inbox placement identifies the folder or category where a controlled provider seed observed the message.

### Can I test Gmail Promotions and Outlook spam placement from Brevo?

Yes. The MailSlurp placement run includes controlled personal and business provider seeds and reports observed results such as primary, promotions, focused, spam, other, or not received.

### Can I use the Brevo Test List for the placement send?

Yes. Add all four active seed addresses as Brevo contacts, include them in the Test List, select all four in **Send test email**, and keep the MailSlurp marker in the message.

### Should I reuse the same seeds next week?

No. Create a fresh MailSlurp run and use its current marker and seed addresses for each campaign revision.

For visual QA, follow the [Brevo Gmail, Outlook, iPhone, and Android preview guide](/guides/brevo-device-rendering/). The dashboard steps and result definitions are also available in the [inbox placement documentation](/docs/inbox-placement/).
