# Implementing BIMI

> Display your brand logo as the sender avatar in supporting inboxes by publishing a BIMI record backed by a DMARC policy and a mark certificate.

BIMI (Brand Indicators for Message Identification) lets you show your logo — and, with the right certificate, a verification checkmark — next to your messages in the inbox. It increases brand recognition and trust, and many major providers now support it.

## Prerequisites

- Establish **verifiable use** of your logo — either a registered trademark, or documented use of the logo for over a year.
- Publish a [DMARC record](https://www.mailblastr.com/docs/domains/dmarc) with a policy of `p=quarantine;` or `p=reject;` (BIMI will not work at `p=none;`).

## Client support

Support depends on the kind of certificate you hold — a Verified Mark Certificate (VMC) or a Common Mark Certificate (CMC):

| Client | With a CMC | With a VMC | No certificate |
| --- | --- | --- | --- |
| Apple Mail | No | Yes | No |
| Gmail | Yes | Yes | No |
| Outlook | No | No | No |
| Yahoo | Yes | Yes | Yes |

## Step 1 — Configure DMARC

BIMI requires an enforced DMARC policy so that no one else can spoof your domain and ride on your logo. The relevant tags:

| Tag | Purpose | Required value |
| --- | --- | --- |
| `p` | Policy | `p=quarantine;` or `p=reject;` |
| `pct` | Percentage | `pct=100;` |

```text
v=DMARC1; p=quarantine; pct=100; rua=mailto:dmarcreports@example.com
```

> **Warning:** For BIMI on a subdomain, the root (apex) domain must also publish a `p=quarantine` or `p=reject` policy. Without it the subdomain is not BIMI-compliant and the logo will not show. If you have not set up DMARC yet, follow [Implementing DMARC](https://www.mailblastr.com/docs/domains/dmarc) first.

## Step 2 — Get a mark certificate

To display your logo in most clients you must prove ownership of it with a mark certificate, much like obtaining an SSL certificate for a website. The two types:

- **Verified Mark Certificate (VMC)** — available if you hold a **trademark** of the logo. Widest support; Gmail shows a blue checkmark alongside the logo.
- **Common Mark Certificate (CMC)** — available if you can show you have **used the logo for at least a year** (no trademark needed). Currently supported mainly by Gmail.

Certificates are issued by authorized mark verifying authorities such as DigiCert, GlobalSign, and SSL.com. Before you start, know that:

- You cannot get a certificate without a trademark *or* a documented year of logo use.
- The process can take weeks — start early and respond to the authority’s requests promptly.
- You will need an **SVG Tiny P/S** formatted logo, a DNS record to prove domain ownership, identification proving you own the trademark/logo, and publicly available proof your business exists.

## Step 3 — Publish the BIMI record

With the certificate in hand, add a TXT record that points to your logo and your certificate:

**TXT record**

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `Name` | host | No | `default._bimi` |
| `Type` | record | No | `TXT` |
| `Value` | string | No | `v=BIMI1; l=link_to_logo; a=link_to_certificate;` |

```text
v=BIMI1; l=https://vmc.example.com/00-00.svg; a=https://vmc.example.com/00-00.pem;
```

> **Warning:** Serve both the logo (`.svg`) and the certificate (`.pem`) over **HTTPS** — providers will not display a logo fetched from an HTTP URL.

It often takes a few days after the record propagates for the logo to appear, and mailbox providers decide whether to show it based on your domain’s sending volume and reputation. A domain with a high spam or bounce rate may not get its avatar displayed.

## Tag reference

| Tag | Purpose | Example |
| --- | --- | --- |
| `v` | BIMI version | `v=BIMI1` |
| `l` | Logo URL | `l=https://vmc.example.com/00-00.svg` |
| `a` | Certificate URL | `a=https://vmc.example.com/00-00.pem` |
| `s` | Selector (for multiple logos) | `s=springlogo` |