Lemlist sequences: seed every campaign

Lemlist built its reputation on the idea that personalised cold email outperforms generic cold email. That is true — when the personalised message actually reaches the inbox. The subtle trap Lemlist users fall into is assuming that a clever liquid template, a dynamic image, or a personalised video somehow boosts deliverability. It does not. Filters never see the rendered creative; they see headers, authentication, content tokens and links. Seed emails are the only way to find out what Gmail, Outlook, Yahoo and the CIS providers actually do with your carefully crafted sequence.

How Lemlist routes your sequence

Understanding Lemlist's send path helps you read seed results correctly. Lemlist does not send through its own infrastructure by default. It connects to your Google Workspace or Microsoft 365 mailbox over SMTP or the provider API and sends as you. That means the Authentication-Results header your seed receives will show your sending domain as the authenticated party — not Lemlist. If DKIM fails on a seed, the problem is your DNS setup, not Lemlist.

Lemlist does inject a tracking pixel and rewrite links for click tracking when those features are enabled. Both are visible in the rendered message at the seed inbox. Both are also visible to spam filters. If placement drops to Promotions at Gmail, the rewritten links and pixel are usually why.

Adding seeds to a Lemlist campaign

The mechanics are straightforward. Seeds are just leads that happen to be mailboxes you control.

1. Open the free Inbox Check tool and generate a batch of 20+ seed addresses. Copy the list.
2. In Lemlist, open your campaign, go to Leads, and click Add leads → Manually or Import CSV.
3. For each seed, add the email and set first name to something that renders naturally in your liquid template (e.g. "Alex"). A blank {{firstName}} token at the top of a cold email is a strong spam signal.
4. Tag every seed with seed so you can filter them out of reply reports later.
5. Save. The seeds will receive every step of the sequence on the same cadence as real prospects.

Per-stage placement: why it matters

Most Lemlist sequences are three to seven steps. Placement is not constant across the sequence. Step 1 is usually the most neutral — short, personalised, low on links. Step 3 and 4 tend to introduce attachments, calendar links, or soft-pitch language. That is the exact moment filters re-evaluate.

• Step 1 seed placement tells you whether the base authentication, domain reputation and opening hook pass.
• Step 3 seed placement tells you whether the softer pitch plus links plus a pixel still pass.
• Final step seed placement reveals whether the "breakup" email — usually blunt and short — has started to look like low-effort spam to Outlook's filter.

A common pattern: Gmail stays 90%+ Inbox through step 5, but Outlook drops from 80% on step 1 to 20% on step 3. That single insight lets you rewrite step 3 instead of tearing down the whole sequence.

Reading Gmail vs Outlook results

Gmail and Outlook behave differently, and Lemlist users need to read each provider on its own terms.

Gmail

Gmail's three folders that matter: Primary, Promotions, Spam. For cold outreach, Primary is the goal. Promotions is not Spam but it is the folder people check once a week. If a step moves from Primary to Promotions, the likely culprits are: too many links, images, unsubscribe footer styled as marketing, or tracking pixel visible at scale.

Outlook / Microsoft 365

Outlook uses Focused vs Other, and Junk for Spam. Focused is the good folder. Other is acceptable for cold outreach — prospects do read it. Junk is fatal. Microsoft 365 consumer and business tenants apply different weight to SmartScreen and to the tracking domain reputation. If a Lemlist campaign lands in Junk at one Outlook seed but Focused at another, the split is almost always SmartScreen reacting to a specific phrase.

Fixing a mid-sequence placement drop

When your step 3 seed report shows Spam at Outlook and Promotions at Gmail, work in this order:

1. Links. Count them. Anything over two links in a 100-word cold email triggers filters. Kill the calendar link on step 3 and move it to step 4.
2. Liquid fallback. If {{company}} renders as empty string for some leads, the sentence becomes grammatically broken and scores as spam. Set a fallback value.
3. Tracking domain. Lemlist's shared tracking domain is hit harder than a custom one. Set up track.yourdomain.com and re-test.
4. Subject line. Replies-only threads with "Re:" prefixes on step 2+ used to help placement. In 2026 Gmail penalises fake-reply subjects. Use a fresh subject on each step.

Frequently asked questions