Lemwarm

Lemwarm is an email warm-up and deliverability monitoring tool built by lempire, the company behind Lemlist, and is widely used as a starting point for cold email senders who need to build or maintain inbox placement.

The tool automates the warm-up process by sending and receiving emails through a network of 20,000+ domains across 150+ countries, gradually building sender reputation while monitoring technical setup, content risks, and deliverability scores.

Lemwarm is best suited for solo senders, small sales teams, and Lemlist users who want a straightforward warm-up solution, with plans starting at $24 per email per month on an annual billing cycle.

Top Features

• Automated warm-up using a network of 20,000+ domains from 150+ countries
• Technical setup checks for SPF, DKIM, DMARC, MX records, and custom tracking domain
• Personalized warm-up emails with custom replies to simulate natural conversation
• Daily deliverability reports covering sender reputation and performance insights
• Spam risk alerts based on sending behavior and email content
• Industry-tailored warm-up network available on the Smart plan
• Real email template warm-up so your actual campaign content gets tested
• Included free with an active Lemlist subscription

Pricing

Lemwarm offers three billing cycles: monthly, quarterly (10% discount), and yearly (20% discount).

The Essential plan costs $29 per month per email ($24/month on annual billing) and includes automatic warm-up, technical setup checks, deliverability reports, and access to the 20,000+ domain warm-up network.

The Smart plan costs $49 per month per email ($40/month on annual billing) and adds personalized warm-up emails, real email template warm-up, custom deliverability alerts, and an industry-tailored warm-up network.

Teams with more than 10 users can contact sales for custom pricing, and Lemwarm is available at no additional cost for users with an active Lemlist subscription.

How Lemwarm Works

Lemwarm operates in three sequential phases designed to build and sustain inbox placement over time.

In the first phase, the tool checks your technical configuration, flagging any missing or misconfigured DNS records such as SPF, DKIM, DMARC, and MX settings before the warm-up begins.

Once setup is confirmed, Lemwarm starts sending automated emails on your behalf to its warm-up network, gradually increasing volume to signal to email providers that your domain is a legitimate, consistent sender.

In the second phase, Lemwarm monitors your sending behavior and content in real time. It watches for patterns that could trigger spam filters, such as sudden volume spikes or flagged language in your copy, and sends alerts when risks are detected.

The Smart plan extends this by warming up your actual email templates, which means the content your prospects will receive is the same content being evaluated during warm-up.

The third phase is ongoing monitoring. Even after the initial warm-up period of three to four weeks, Lemwarm recommends keeping the tool active throughout your campaigns.

Stopping warm-up after the initial phase can create irregular sending patterns, which email providers interpret as a negative signal and which can push future emails toward spam.

Lemwarm and Lemlist Integration

Lemwarm was built as a companion product to Lemlist, and the integration between the two is seamless.

Users with an active Lemlist subscription can access Lemwarm at no additional cost, making it one of the most cost-effective warm-up options for teams already using Lemlist for outreach.

The shared infrastructure means deliverability data from Lemwarm can inform campaign decisions made inside Lemlist without requiring manual data transfers or third-party connections.

For teams not using Lemlist, Lemwarm still functions as a standalone tool and supports any email provider that allows IMAP and SMTP access, including Gmail, Google Workspace, Microsoft 365, and others.

What Lemwarm Does Not Cover

Lemwarm is transparent about its scope.

The tool focuses on warm-up automation and deliverability monitoring but does not offer true inbox placement testing, which is the ability to send a test email and see whether it lands in the Primary inbox, Promotions tab, or Spam folder across real Gmail and Outlook accounts. Its spam detection is based on content analysis and behavioral signals rather than live seed inbox results.

Teams that need that level of diagnostic depth may want to evaluate tools like MailReach or Warmy alongside Lemwarm, or use a dedicated spam testing tool in combination with Lemwarm's warm-up features.

Additionally, Lemwarm's warm-up network, while large in domain count, is not exclusively composed of Google Workspace or Microsoft 365 business inboxes.

For B2B cold outreach where Gmail and Outlook engagement signals carry the most weight with inbox providers, this is a meaningful distinction compared to tools that specifically curate their networks around those two providers.

Who Should Use Lemwarm

Lemwarm is a practical choice for individuals and small teams who are new to cold email and need a reliable, low-friction warm-up tool. Its tight integration with Lemlist makes it especially valuable for existing Lemlist customers who want to consolidate their stack.

The Essential plan covers the fundamentals well, and the Smart plan adds enough personalization to satisfy senders who want their actual templates evaluated during warm-up.

Growing agencies or teams managing many inboxes across multiple clients may find Lemwarm's diagnostics less detailed than dedicated deliverability platforms, and should evaluate whether the custom pricing tier meets their operational needs before committing.

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