Lemwarm Alternative: Free Warm-Up for Up to 20 Mailboxes

If you need a Lemwarm alternative for non-Outlook mailboxes, BobWork Email Warm-up is free for up to 20 mailboxes per account, while Lemwarm Essential lists at $29 per email address monthly. Ignoring per-address pricing can turn 20 senders into $580/month. This guide compares cost, pool type, provider fit, limits, and a safe switch plan.

Prices were read on 3 October 2026 from the vendor’s pricing page; check before you buy.

Which lemwarm alternative fits?

Lemwarm is the warm-up product associated with lemlist. Its cheapest listed paid plan is Essential at $29 per email address monthly, or $24 per address monthly on annual billing. The Smart plan is listed at $49 monthly, or $40 monthly on annual billing.

BobWork Email Warm-up is different in three practical ways. It is free, it supports up to 20 mailboxes per account, and it lets you choose a shared network or a private pool per account.

The private-pool option is not the same as a shared warm-up network. For the mechanics, read our guide to how email warm-up networks work. The short version: shared networks trade volume and variety for less control over who your mailbox talks to.

The biggest difference is the operating model.

With Lemwarm, your mailbox joins a shared network. Its pricing page states “20,000+ real domains in 100+ countries.” That can be useful if you want many external domains and do not mind a shared network.

With BobWork, the shared network is the default. Switch the account to Private pool (at least two mailboxes) and nobody else’s inbox receives your addresses, and your inboxes do not warm strangers.

When is Lemwarm better?

Stay with Lemwarm if you use Outlook or Microsoft 365 today. BobWork Email Warm-up does not support Outlook yet. Microsoft requires OAuth, and BobWork has not shipped that connection.

Lemwarm also lists Gmail and Outlook one-click connection. BobWork supports Gmail and Google Workspace through Google sign-in, but Google shows an unverified-app notice because BobWork has not completed the CASA audit. You can also connect Gmail with IMAP and an app password.

Lemwarm states a network size; BobWork does not publish one. Its pricing page states “20,000+ real domains in 100+ countries.” If your priority is a broad shared network, that is a real advantage.

Lemwarm may also be simpler if you already use lemlist. The listed trial information says lemlist offers 14 days no card and bundles lemwarm. If outreach, inbox connection, and warm-up already live in that workflow, staying can reduce admin.

Provider coverage can be another reason to stay. Lemwarm mentions Proton and FastMail. BobWork supports any IMAP+SMTP mailbox, but the named provider lists are not identical. Check your provider’s current IMAP and SMTP rules before switching.

What does BobWork change?

BobWork’s strongest advantage is cost. You can connect up to 20 mailboxes per account for $0. There is no credit card, no time limit, and no paid tier required for the warm-up engine described here.

The second advantage is pool control. Any account can switch to a private pool where only mailboxes inside your account write to each other.

That changes setup. A private pool needs at least two mailboxes. It works best when your mailboxes are not all identical. BobWork chooses peers on a different domain or provider twice as often when those peers exist.

BobWork also handles rescue mail. Warm-up mail found in Spam is moved to Inbox, marked read, labelled “Warm-up”, and archived after 24 hours. Only mail carrying the engine’s hidden header is touched. For Zoho API senders, BobWork uses a known subject. Real mail is never read, moved, or answered.

Measurement is direct. BobWork measures spam landings inside the receiving mailbox, not through third-party seed lists. Spam rate means the share of a sender’s warm-up mail that receiving mailboxes found in Spam over 7 days.

The health score runs from 0 to 100. Healthy is 85 or higher. Watch is 60–84. At risk is under 60. Blocked means login or permission failed.

A mailbox is ready for outbound after 14 or more days of warming, a 7-day spam rate of 3% or lower, and at least 30 warm-up emails received. If this is your first warm-up, read what to expect during the first warm-up.

How much does each option cost?

Per-address pricing looks small at one mailbox. It changes when you add sender identities, regions, founders, SDRs, or brand domains.

This table uses Lemwarm Essential monthly pricing at $29 per email address. It also shows the annual-billing equivalent at $24 per address monthly. It does not include Smart, because this comparison uses the cheapest listed paid plan.

The 20-mailbox row matters because it is BobWork’s account limit. If you need exactly 20 supported mailboxes, the difference is the full per-address line item.

Cost should not be the only factor. Outlook support, your current workflow, and your tolerance for shared networks matter. But if your main issue is paying per address for warm-up, the free option is materially different.

You can estimate a safe ramp with our warm-up schedule generator. For most campaigns, we publish conservative practice: warm an existing domain for 14 days, and warm a new domain for 3–4 weeks.

During active campaigns, keep warm-up at 10–15 emails per day and keep real outreach around 30–50 emails per day per mailbox. Add mailboxes before you add volume. Pause a mailbox for a few days if its spam rate rises above 5%.

Who should not switch?

Do not switch if you use Outlook or Microsoft 365 today. BobWork does not support those providers yet, so it is not a direct replacement for a Microsoft-heavy stack.

Do not switch only to save money if lemlist is already your main outbound system and the workflow works. Tool consolidation has value when it removes daily admin.

Do not switch if you want a shared network by design. Lemwarm states a shared network of “20,000+ real domains in 100+ countries.” BobWork’s shared network does not publish a size claim.

Do not switch without checking provider access. Lemwarm mentions Proton and FastMail. BobWork supports any IMAP+SMTP mailbox, but provider rules change. Check the provider’s current limits and connection requirements.

Do not switch if your internal approval process already cleared Lemwarm and security review time is scarce. Email access tools can require review. Cost savings may not justify a rushed change if the current setup is stable.

Also stay if you need a Lemwarm feature not covered here. This page uses only the competitor facts listed from the vendor’s pricing page. If your decision depends on a feature not shown there, verify it with Lemwarm directly.

How do you switch safely?

Do not disconnect everything at once. Warm-up is behavioural. Keep the move slow, boring, and measurable.

1. List your senders

Write down each mailbox, provider, domain, and current daily outreach volume. Include aliases only if they send real outbound mail. Warm the mailbox that sends, not just the domain.

Check whether each mailbox is supported by BobWork. Supported options include Gmail and Google Workspace, Zoho Mail, Lark Mail, Yahoo Mail, iCloud Mail, Amazon SES, SendGrid, Mailgun, and any IMAP+SMTP mailbox.

Outlook and Microsoft 365 are not supported yet. Microsoft documents the OAuth model for Microsoft identity platform apps in its authorization code flow guide.

2. Check authentication

Before you move warm-up, check SPF, DKIM, and DMARC. Authentication does not guarantee inbox placement, but missing records make reputation work harder.

BobWork checks SPF, DKIM, and DMARC daily via DNS and shows results per domain. DKIM selector detection covers common selectors including google, zmail, default, selector1, selector2, k1, s1, mail, dkim, lark, feishu, and zoho.

You can also use the standalone SPF checker, DKIM checker, and DMARC checker before connecting mailboxes.

For Google Workspace, Google documents Gmail API authorization and scopes in its Gmail API scopes guide. BobWork’s Google sign-in uses the gmail.modify scope. Google shows an unverified-app notice because BobWork has not completed the CASA audit.

3. Connect two mailboxes

A private pool needs at least two mailboxes; on the shared network one is enough.

For Gmail or Google Workspace, use Google sign-in or IMAP with an app password. For Zoho Mail, use the Zoho Mail API through a Self Client code, which works on the free plan. Zoho documents that flow in its Self Client guide.

For Zoho IMAP, use Mail Lite or higher. For Lark Mail, use IMAP with a mail-client password. For Yahoo Mail and iCloud Mail, use IMAP with an app password. For Amazon SES, SendGrid, and Mailgun, use SMTP credentials for sending and the receiving inbox over IMAP.

4. Start the default ramp

Use the default ramp first. It starts at 3 emails per day, adds 2 per day, and caps at 30 per day. That is enough for a normal baseline.

Do not raise caps just because the tool allows it. If you are warming for outreach, keep warm-up at 10–15 per day during campaigns and keep real outreach at 30–50 per day per mailbox.

The free pool does this step automatically: it spreads sends across 09:00–18:00 in each mailbox’s time zone, adds randomness, avoids repeat pairings within 3 hours, and favours different domains or providers when available.

5. Watch seven-day spam rate

Do not judge the switch on day one. Use the 7-day spam rate and health score.

BobWork defines spam rate as the share of a sender’s warm-up mail that receiving mailboxes found in Spam over 7 days. Healthy is 85 or higher. Watch is 60–84. At risk is below 60.

A mailbox is ready for outbound when it has warmed for at least 14 days, has a 7-day spam rate of 3% or lower, and has received at least 30 warm-up emails.

If spam rate rises above 5%, pause that mailbox for a few days. Fix authentication, reduce outbound volume, and check whether recent campaigns caused complaints. Google’s sender guidance says to keep spam complaint rates under 0.1% and avoid ever reaching 0.3% in its email sender guidelines.

6. Move campaigns gradually

When a mailbox is ready, do not jump straight to high outbound volume. Keep outreach conservative. A typical safe range is 30–50 real emails per day per mailbox, provided the list is clean and replies are normal.

If you need more total volume, add mailboxes rather than forcing one sender to do too much. That keeps per-mailbox behaviour closer to a normal human pattern.

If you want more background on spam causes, read why emails go to spam. Warm-up is one part of delivery. It does not fix poor targeting, bad lists, weak authentication, or high complaints.

What should you do now?

Use this checklist before you cancel any paid tool. It keeps the switch reversible.

Keep Lemwarm if Outlook support, lemlist bundling, or a large shared network matters more than cost. Try the free warm-up tool if you use supported providers, and do not want to pay per email address for mailbox warm-up.

Frequently asked questions