TL;DR: Set your lemwarm daily limit to the volume the mailbox will actually send in lemlist later — for a new mailbox that is 30–40 emails/day — keep lemlist at 0 while warm-up runs, and let lemwarm build the reputation first. Ramp-up takes about 40 days at +1/day, then 14 days of stabilization at target before the first campaign launches.
Who Should Use This
New lemwarm users who want to connect and warm up one or more sending inboxes
Sales teams, founders, and recruiters preparing an email account for outreach
Anyone who wants to improve email deliverability before increasing sending volume
Why This Matters
lemwarm helps you build and maintain your email sender reputation over time. If you set it up correctly and increase sending volume gradually, you improve your chances of landing in the inbox, reduce the risk of spam placement, and catch deliverability issues early.
Key Concept
The warm-up target must match your future lemlist volume: decide how many emails a day this mailbox should send once it is live, then set that number as your warm-up value. For a new mailbox the recommended range is 30–40/day.
Do not use a fixed default: warming a mailbox to 16/day when it is meant to send 35/day trains it for the wrong job. The same applies in reverse — do not warm to 40 a mailbox that will only send 20.
A new mailbox has three phases, not one volume: ramp-up (lemwarm only), stabilization (lemwarm only, 14 days), then active sending (lemlist 30–40/day + lemwarm 10/day).
No cold sending during warm-up: keep lemlist at 0 until the warm-up score reaches 90+ and stabilization is complete.
Never increase sending all at once: the ramp-up increment for a new mailbox is 1.
lemwarm works best when left on continuously: after launch it drops to a residual 10/day whose only job is to report reputation.
You can connect multiple sending addresses: add more addresses from the same person to distribute sending volume safely across inboxes.
Before you begin, decide which email address you want to warm and what daily volume it should reach in lemlist, because that answer is your warm-up value.
Step-by-Step Guide
Choose a lemwarm plan and manage billing. From the dashboard, click your profile icon and select Settings
Then open Billing & Users and click Manage in the Subscription section
On the pricing page, choose the plan that matches your needs
Open your sending settings. From the dashboard, click your profile icon, select Settings, open Sending settings, expand the Email section if needed, and click Connect email address.
Connect the email account you want to warm. Review the connection rules, click Accept and continue, then choose your provider: Google / Gmail, Microsoft / Outlook, or Other email provider (SMTP/IMAP).
Connect multiple sending addresses if needed. You can repeat the same flow to add more sending addresses for the same user so lemwarm can distribute sending volume over multiple inboxes. Only connect addresses that belong to the same person and that you are authorized to use.
Verify the email address. Complete the verification step so lemwarm can start sending warm-up emails and handle replies for that inbox.
Start lemwarm from the dashboard. Once the inbox is connected, go to the dashboard and click Start lemwarm, then click Confirm.
Set your warm-up value to your target lemlist volume. Ask yourself how many emails a day this mailbox should send once it is live, then enter that number. For a new mailbox the recommended range is 30–40/day. Keep the Ramp-up increment at 1.
Keep lemlist at 0 during warm-up. No cold sending while the mailbox is ramping up or stabilizing. The only traffic leaving the mailbox in this period is lemwarm.
Let the ramp-up run about 40 days. At a ramp-up increment of 1, lemwarm adds one email per day until it reaches your target. That takes roughly 40 days (about 20 days at an increment of 2, which is only appropriate for an older mailbox).
Hold at target for 14 days of stabilization. This period is non-negotiable. Keep lemwarm at your target volume and lemlist at 0, and confirm your inbox rate stays above 90% for 14 straight days. If spam appears during that window, the clock restarts.
Monitor performance and manage warm-up directly from the Warm up tab. Open Warm up from the left sidebar to review each connected inbox, adjust limits, check the score, and stop warm-up when needed.
Organize lemwarm emails outside your main inbox. To avoid clutter, create a filter in your email provider to automatically move lemwarm emails out of your primary inbox.
Important: A mailbox paused for more than 7 days goes back through a short ramp before resuming cold sends. In recovery, the ramp increment is 3, not 1 — a mailbox rebuilding trust is not a new mailbox.
When to Start Sending Campaigns
No campaign starts under a warm-up score of 90. Check your score in the lemwarm dashboard and follow the guidance below.
Score below 65 — Pause and investigate
Do not send any email campaigns through lemlist or other platforms
Pause lemwarm temporarily
Check your DNS records (SPF, DKIM, DMARC) and verify your domain is not on any blacklists
Fix any domain or reputation issues before restarting warm-up
Score between 65 and 90 — Warm up only, no campaigns
Send emails only through lemwarm during this period — no lemlist campaigns
Set your target daily volume based on what the mailbox will send in lemlist (30–40/day for a new mailbox)
Set your warm-up value to match that target and keep the ramp-up increment at 1
Hold that volume for the full 14-day stabilization period without triggering spam filters
Monitor your score and avoid any sudden increases in sending volume
Score above 90 — Ready to start campaigns
Once the score is 90+ and you have completed 14 days of stabilization with an inbox rate above 90%, you can begin sending lemlist campaigns
Open lemlist at 30/day, not at your full target. Move to 40/day once a month of clean sending is behind the mailbox
Drop lemwarm to 10/day at the same time. Those 10 emails are no longer warming anything — they report reputation
Between two numbers inside the 30–40 range, take the lower one. Low and stable beats high and aggressive
Absolute ceiling: total output — lemlist + lemwarm + manual replies — stays under 70/day per provider in every case. A customer answering 15 prospects by hand is using 15 of that budget. The ceiling is per provider, not per mailbox: six Google mailboxes share one Google-side reputation, not six independent budgets.
How You'll Know It Worked
✓ Your email account is connected and verified in lemwarm
✓ Warm-up emails begin sending after you click Start lemwarm
✓ Your warm-up value matches the volume the mailbox will send in lemlist
✓ You reach your target in lemwarm in about 40 days at an increment of 1
✓ After 14 days at target with an inbox rate above 90%, your score is 90+
✓ Your spam rate stays around 1–2% maximum
Understanding Your Reports
Your lemwarm dashboard helps you track whether warming is improving your deliverability. Use it regularly to spot issues before they affect your outreach.
lemwarm score: shows the overall health of your email deliverability
Inbox vs. spam results: shows how many emails are landing in the inbox compared with the spam folder
Cold Email Performance graph: tracks sent emails and shows inbox placement in green versus spam placement in red
Reply Performance graph: tracks whether replies to your emails are landing in the inbox or spam folder
After 14 days at target volume with no spam, expected results are:
Deliverability score over 90
Spam rate of 1–2% max
Because lemwarm emails contain no links and no images, there is normally no reason for them to land in spam at a higher rate.
How the lemwarm Score Works
The score is a weighted composite of four components. Knowing the weights changes how you read a drop.
Technical setup — 50%. SPF, DKIM and DMARC present and valid on the sending domain. Moves instantly, once DNS propagates.
Spam rate — 30%. Inbox versus spam placement on warm-up traffic, weighted 1 spam = 5 inbox. Moves in days. This is what changes week to week.
Mailbox age — 10%. How long the mailbox has existed. Moves in months, and only upward.
Blacklist — 10%. Domain or IP appearing on a major blacklist. Moves overnight, in both directions.
How to read it:
A score that falls week to week is almost always the spam-rate component. Look at content, targeting and volume — not at DNS.
Because 50% of the score is DNS, a mailbox with clean SPF, DKIM and DMARC sits around 50 before sending anything. A mailbox with broken DNS is capped near 50 however well it sends.
A score of 80 is not an 80% inbox rate. It is a weighted composite, and should never be quoted as a placement percentage.
The 1 spam = 5 inbox weighting is why the score reacts fast and why small samples swing it. A handful of spam placements moves the number more than the raw ratio suggests.
Below 80 in steady state means a reputation problem. Below 65, pause and investigate.
Transitioning from lemwarm to lemlist
Once the score is 90+ and the 14-day stabilization is behind you, reduce lemwarm to 10/day and open lemlist at 30/day.
That is a combined output of about 40/day in the first month or two. Once a month of clean sending is behind the mailbox, move lemlist to 40/day, for a combined output of about 50/day.
30–40/day is the lemlist maximum for a new mailbox, not a starting point to grow from in week one. Open at 30, and only move to 40 with clean signals behind you.
Monitoring Reputation Once Campaigns Are Live
Once campaigns are live, the residual 10/day of lemwarm is no longer warming anything. Its only job is to tell you whether the mailbox and its domain still have a good reputation. There is a cleaner instrument for that, and you should always have one of the two in place.
Inbox placement tests — recommended. Run 1 to 2 per month, no more. They measure where your actual campaign content lands, per receiving provider. Do not test weekly: placement varies day to day for reasons outside your control, so one or two reads a month give you a trend while four give you arguments.
lemwarm at 10/day — fallback. If you will not or cannot run inbox placement tests, keep lemwarm at 10/day as the early-warning signal instead.
The two are not equivalent. Inbox placement tests the real email; lemwarm tests the mailbox. When you run both, inbox placement is the one that decides. Test the real campaign from a real sender in the account — a clean test on a template nobody sends proves nothing.
Never neither. If you drop lemwarm entirely and run no placement tests, you have no early warning at all. That is the one configuration we push back on.
Why Keep lemwarm Running While Sending with lemlist
Continuity: if your lemlist campaign ends and there are no more leads to contact, the email account is still active and sending
Early warning system: if your reputation starts to decline in lemlist because of bad copywriting, poor setup, or another sending issue, the lemwarm score drops and you see it before the reply rate moves
Keeping 10 lemwarm emails/day active gives you that signal. If spam starts increasing in lemwarm, that is a sign that lemlist activity may be hurting the mailbox reputation. If that happens, lower lemlist volume or stop lemlist entirely until performance recovers.
When to Pause lemwarm
Pause lemwarm only if the sending habits in lemlist are seriously damaging the mailbox reputation and polluting the lemwarm pool.
In that case:
Pause lemwarm for 1–2 weeks
Fix the sending issues in lemlist
Restart at about 15/day lemwarm + 15/day lemlist (roughly 30/day total) with a ramp increment of 3, and keep both reputation signals running until the mailbox is stable again
You can also stop warm-up directly from the Warm up tab for a connected inbox when you need to pause activity temporarily.
Troubleshooting
Issue: Deliverability is not improving after a few days
Root cause: Email warming takes time, and the inbox may still be in the early reputation-building phase.
Fix:
Expect about 40 days of ramp-up at an increment of 1, plus 14 days at target
Keep lemlist at 0 for that whole period
Increase volume gradually instead of all at once
Issue: Your lemwarm score is below 90 even after reaching target volume
Root cause: A falling or stuck score is almost always the spam-rate component, or DNS capping the score near 50.
Fix:
Review domain setup — SPF, DKIM and DMARC account for 50% of the score
Stay at the same lemwarm volume longer and watch the spam rate
Do not launch campaigns until the score is 90+
Issue: Someone told me to warm to 40 and someone else told me to warm to 16
Root cause: Neither number is a default. The warm-up value is decided by the volume the mailbox will actually send.
Fix:
Decide the target lemlist volume first — for a new mailbox, 30–40/day
Set the warm-up value to that number
Check domain age before raising an existing value: pushing 16 to 40 on a two-week-old domain makes things worse, not better
Issue: Your inbox is filling up with lemwarm emails
Root cause: No inbox filter has been set up for warm-up emails.
Fix:
Create a filter in your email provider to automatically sort lemwarm emails
Move those emails out of your primary inbox view
Review your provider's filtering rules if emails are still appearing in the main inbox
Issue: You need to warm more than one sending address
Root cause: Only one inbox has been connected so far.
Fix:
Go to Settings → Sending settings
Click Connect email address and repeat the connection flow
Remember the volume ceiling is per provider, so extra mailboxes on the same provider do not each get a fresh budget
Issue: Leads are marking outreach emails as spam
Root cause: The issue may come from email content, subject lines, sending limits, or lead quality rather than warm-up alone.
Fix:
Reduce your daily outreach volume temporarily
Review and improve your email copy and subject lines
Check the quality and relevance of your lead list
Run an inbox placement test on the real campaign to see whether the problem is content or infrastructure
Best Practices
Set the warm-up value to the volume the mailbox will send in lemlist — 30–40/day for a new mailbox
Keep the ramp-up increment at 1 for a new mailbox, and 3 only in post-incident recovery
Keep lemlist at 0 until the score is 90+ and stabilization is done
Open lemlist at 30/day and drop lemwarm to 10/day on launch day
Never quote a volume without naming the phase, and give the total before the split
Keep total output — lemlist + lemwarm + manual replies — under 70/day per provider
Keep one reputation signal at all times: inbox placement 1–2 per month, or lemwarm at 10/day. Never neither
Between two numbers inside the range, take the lower one