MailerLite: free newsletter tool + free inbox placement test

The free-tool newsletter stack looks great on paper and runs into one wall in practice: you can send for free, you can design for free, you can track opens and clicks for free, but you cannot see where your emails actually land. Dashboards everywhere call a message "delivered" whether it reaches the inbox, Promotions, or Spam. Subscribers only read the inbox version. Which means the most important metric in your whole stack — placement — is the one missing from the free tier of every ESP.

MailerLite is the most generous free ESP on the market. Inbox Check is a free, unlimited inbox placement tool. Used together they close the placement gap without adding a paid line item. This guide shows exactly how to wire them together for a weekly newsletter.

What MailerLite free actually includes

Before wiring seeds, confirm the free-tier limits. As of the current plans, the MailerLite free tier includes:

• Up to 1,000 subscribers (seeds count toward this).
• 12,000 emails per month.
• Drag-and-drop editor, templates, signup forms.
• Basic automation (welcome email, birthday, etc.).
• Open and click tracking, campaign reports.

That is enough for most indie newsletters, nonprofit lists, and side projects to run indefinitely without upgrading. The only thing it does not include is inbox placement reporting. Even on paid tiers, MailerLite reports delivered vs. bounced — not inbox vs. spam. No ESP reports this, because no ESP can see into its recipients' mailboxes. This is what seed addresses solve.

Adding seed subscribers to MailerLite

Seeds are just subscribers with a label. MailerLite's term is Group (equivalent to Mailchimp's Segment or Brevo's List). Create one group for seeds and one group per real audience segment:

1. In MailerLite, go to Subscribers → Groups → Create group. Name it seeds.
2. Generate a batch of seed addresses. The free Inbox Check tool produces 20+ per run covering Gmail, Outlook, Yahoo, Mail.ru, Yandex, GMX, ProtonMail, and more.
3. Import the seeds: Subscribers → Add → Import from CSV. Assign them to the seeds group. Skip the double opt-in confirmation (these are your own test inboxes, and Inbox Check pre-confirms them).
4. Build a combined group for newsletter sends: audience + seeds. Every campaign goes to that combined group.

The pre-test-then-send workflow

The habit that turns the free stack into a proper deliverability pipeline is a two-step publishing flow: test first, send second. Both steps happen inside MailerLite's UI.

1. Draft the newsletter in MailerLite as normal.
2. Send to seeds only. Use MailerLite's "Schedule → send now" on the seeds group alone. Wait two minutes.
3. Read the Inbox Check report. It should show 90%+ inbox placement across the major providers. SPF/DKIM/DMARC all pass. No spam-filter warnings on the content.
4. If the report looks clean, schedule the real send to the audience group. If it does not, edit the email (subject, body, links, or images) and re-seed.

On the free tier you get 12,000 emails per month. Seeding a list of twenty costs twenty emails per test. Even if you test four versions of each weekly newsletter that is 320 emails out of your quota — under 3%. The math works.

Common MailerLite placement issues and what to do

Seed reports surface a handful of recurring problems on MailerLite newsletters. Most are fast to fix once you see them:

Gmail lands in Promotions tab

Seeds report inbox but placement field says Promotions. This is Gmail tabbing, not spam. For newsletters this is often acceptable, but if you want Primary tab: remove multiple links per paragraph, cut image-to-text ratio below 40%, and avoid promotional keywords in the subject.

Mail.ru drops to Spam while Gmail is fine

Mail.ru is Russia-centric and stricter than Gmail on Cyrillic content, link-shorteners, and non-aligned DMARC. If your list includes Russian subscribers, fix the Mail.ru verdict even if Gmail looks clean. Usual fix is a text/plain fallback and authenticated From-domain.

DKIM fails intermittently

MailerLite signs with its own keys by default. If you switched to a custom sending domain and forgot to add the MailerLite DKIM CNAME, half your mail will fail. The Inbox Check auth report points to the missing record. Add the CNAME in your DNS provider, wait for propagation, re-seed.

Scaling beyond the free tier

The zero-cost stack works up to roughly 1,000 subscribers and one newsletter per week. Past that you either pay MailerLite ($10 to $30/month for up to a few thousand subscribers) or pay for higher-volume seed checks. The paid inflection point is usually when either:

• Your list exceeds 1,000 real subscribers (hits MailerLite free cap).
• You send more than one campaign per week and want automated placement monitoring without firing the test yourself each time.

Until one of those kicks in, the MailerLite free tier plus free Inbox Check is the best indie-newsletter stack on the market.