Mailjet is an email platform handling both marketing campaigns and transactional email on a single account. Sinch acquired it in 2019 – the same parent company as Mailgun – and Mailjet occupies a similar market position to Brevo: a marketing-first platform with SMTP relay and API access for transactional email alongside.
The free tier sends 6,000 emails per month (200/day cap) with full SMTP and API access. That is enough for most low-volume WordPress sites. The catch: free-tier emails carry the Mailjet logo, which looks unprofessional on transactional messages from a business domain. Removing it requires the Essential plan at $17/month.
SMTP settings
| Setting | Value |
|---|---|
| Host | in-v3.mailjet.com |
| Port | 587 (TLS, recommended) |
| Encryption | TLS |
| Authentication | Login |
| Username | Your Mailjet API key |
| Password | Your Mailjet secret key |
Alternative ports: 465 (SSL) and 25 (often blocked by hosting providers).
Generate SMTP credentials in the Mailjet dashboard under SMTP and SEND API Settings in the Senders & Domains section. These are the same API key and secret key used for Mailjet’s API – unlike Mailgun, which uses separate per-domain SMTP credentials.
Add Mailjet’s SPF and DKIM records to your domain’s DNS before sending production email. After configuring DNS, verify with swaks that messages authenticate correctly.
Pricing
Mailjet’s pricing covers both marketing and transactional email in a single volume allocation. There is no separate transactional tier.
| Plan | Price | Volume | Notes |
|---|---|---|---|
| Free | $0 | 6,000 emails/mo (200/day) | Full API/SMTP. Mailjet logo on emails. No credit card. |
| Starter | $9/mo | 8,000 emails/mo | 2,000 contacts. Basic support. Logo still present. |
| Essential | $17/mo | 15,000 emails/mo | Logo removed. Unlimited contacts. Segmentation. 500 email validations. |
| Premium | $27/mo | 15,000 emails/mo | A/B testing. Marketing automation. |
Annual billing saves 10%.
For WordPress transactional email only, the free tier’s 6,000/month is workable for small sites. The 200/day cap is the practical constraint – a WooCommerce store sending order confirmations, shipping notifications, and password resets draws from the same pool as any marketing campaigns on the account. For comparison, Brevo’s free tier allows 300/day (9,000/month equivalent) without forced branding.
WordPress integration
Three paths:
Mailjet WordPress plugin – “
Mailjet for WordPress” connects via API. The plugin replaces wp_mail() and routes WordPress email through Mailjet’s API. It also includes contact list management and campaign features from the Mailjet dashboard – useful if you run marketing campaigns through Mailjet alongside transactional email.
WP Mail SMTP – WP Mail SMTP includes a native Mailjet integration. Select “Mailjet” as the mailer, enter the API key and secret key. This is the better choice if you want WP Mail SMTP’s email logging and fallback features without the marketing plugin overhead.
Generic SMTP – Any mailer plugin (Post SMTP, FluentSMTP, or WP Mail SMTP in “Other SMTP” mode) can connect to in-v3.mailjet.com using the credentials above. This path works when Mailjet is just the relay.
Assessment
Mailjet is a functional SMTP relay for WordPress with a decent free tier. It is not a standout choice in any particular dimension.
The free tier’s 6,000 emails/month handles low-volume WordPress transactional email, but the forced Mailjet branding on those messages is a problem for professional sites. Brevo’s free tier is more generous (300/day, no branding) and offers the same marketing-plus-transactional combination. SMTP2GO’s free tier (1,000/month, 200/day cap) is smaller in volume but has no branding and is purpose-built for transactional email.
Mailjet makes sense for WordPress sites that already use it for marketing campaigns – routing transactional email through the same platform consolidates operations. For sites choosing a new SMTP relay from scratch, Brevo or SMTP2GO are stronger defaults.
The Sinch corporate relationship with Mailgun is worth noting: same parent company, different products. Mailgun is developer-focused infrastructure; Mailjet is a marketer-oriented platform. If you are choosing between them for a WordPress site, Mailjet’s free tier and simpler setup make it the more practical option – though neither is the first recommendation for typical WordPress transactional email.
For the broader setup that places Mailjet inside the WordPress email stack, see the WordPress email setup guide.
Pricing verified June 2026. SMTP settings verified against Mailjet documentation.