Safe daily cold-email volume after warmup

Once a mailbox is warmed up, send 30–50 cold emails a day from it — 50 is the default WarmySender sets. A brand-new sending domain is held to 200 emails a day in total across every mailbox on it (warmup included) until it is at least 30 days old with 200 emails behind it and no spam complaints; after that the ceiling lifts to 2,000 a day. Warmup itself starts at one email a day and reaches full speed around your sixth week of sending days. To send more, add mailboxes — never push a single mailbox higher.

The week-by-week table lives on one page, and this is not it. For the volume by domain age — what warmup sends, what we recommend for cold, and the ceiling the platform actually enforces at each stage — read how many cold emails can I send per day. That page is the canonical answer, and every number on this page is that page’s number. This page covers what it does not: running warmup alongside your cold sending day to day, what the tagged warmup mail in your inbox is, and what happens when a mailbox’s spam rate climbs.

WarmySender runs your outreach on autopilot with AI agents, across Cold Email, Email Warmup, LinkedIn, Instagram and Multichannel sequences — plus real-time email verification.

How much cold email can I send per day per mailbox?

30–50 a day per mailbox once it is warmed up, and 50 is the default. That is a recommendation, not a limit the platform applies: your per-mailbox daily limit is yours to set anywhere from 1 to 500, and nothing stops you raising it. The limits that are applied sit elsewhere — on your domain, on your per-mailbox total, and on your plan — and the lowest one wins on any given day.

You will not find a per-provider version of this number, because none exists. Neither Google, Microsoft nor Yahoo publishes a per-mailbox daily cold-email limit, so any table telling you “Gmail 30–50, Outlook 20–40, Yahoo 20–30” is someone’s guess dressed as a provider rule. What the providers do publish is in the next section, and it is about authentication and complaint rate, not volume per mailbox.

Scale by adding mailboxes, not by overloading one. If you need 200 cold emails a day, that is far safer as four or five mailboxes at 50 a day than one mailbox at 200 — ideally across more than one sending domain. WarmySender always paces sends across your day and sending window rather than firing everything at once, because a sudden burst is one of the strongest signals to a mailbox provider that a sender is automated. And on a young domain extra mailboxes buy you nothing: a domain under 30 days old is held to 200 a day however many mailboxes sit on it, so a fifth mailbox just splits the same 200 five ways.

What do Google, Microsoft and Yahoo actually publish?

Less than the internet claims. All three publish authentication and complaint-rate rules; none publishes a per-mailbox daily sending limit, and none publishes a day-by-day warmup schedule. Their own pages are linked so you can check.

Notice what is not on that list: a required warmup period, a required health score, a required number of days before your first campaign. Those are industry conventions — good ones — but no provider mandates them, and anyone showing you a “day 1: 5 emails, day 2: 8 emails” table attributed to Google is showing you something Google never published.

Should I keep warmup running while I send cold email?

Yes — leave warmup on permanently. Reputation is not a finish line you cross once; mailbox providers keep re-evaluating it as a running average. Warmup keeps a steady flow of genuine, wanted email moving to and from your mailbox, which holds your reputation steady on the days your cold sending is heavy and cushions the impact if a batch of cold email draws a few complaints. Turning warmup off once you are “done” removes that safety net exactly when your cold volume is highest.

You do not have to pick a number. Once a mailbox is established, warmup settles into maintenance on its own and holds a steady level of around 30 emails a day; you can adjust the target per mailbox if you want to. What matters is that it does not drop to zero.

Warmup and cold share one budget. Each mailbox has a single daily total covering both — between 200 and 500 a day depending on your plan — so a mailbox running 30 warmup emails has 30 fewer to spend on campaigns. On a new domain the 200-a-day domain ceiling counts warmup too, which is the usual reason a young domain has less room for campaigns than its owner expects.

How long does warmup take before I can start cold sending?

A new domain reaches full warmup speed — 40 emails a day — around the sixth week of sending days. WarmySender starts it at one email a day and steps up roughly one more a day: around 7 a day by the end of week 1, 15 by week 2, 21 by week 3, 35 by week 5, and 40 around week 6. A mailbox on an already-established domain starts higher and can reach 60.

Count sending days, not calendar days. Warmup only advances on days the mailbox actually sends, so a mailbox that spent a week disconnected is a week behind where the calendar says it is.

Nothing blocks you from starting a campaign sooner. There is no warmup gate on cold sending — you could launch on day one. We recommend waiting until warmup has run about three weeks of sending days first, and we would rather say plainly that this is guidance than pretend there is a gate where there is not one. The ramp itself cannot be hurried, and trying is what damages a young domain: Google’s own advice is to increase slowly, and suddenly doubling the volume you previously sent is the one shape to avoid.

The full curve and what changes it: how warmup ramps up.

What is the warmup mail in my inbox — does it mix with real replies?

Warmup email lands in your inbox by design, it is clearly tagged, and it is tidied away automatically within about a day — so any untagged reply you see is a real person. For warmup to build reputation, some of it has to arrive in an inbox and be interacted with, the way a normal, wanted email would. Every warmup message carries a tag you can recognise and filter on, and WarmySender clears warmup mail out for you shortly after it arrives.

Warmup health is measured separately from your cold results. How reliably your warmup reaches the inbox is calculated from warmup activity alone, and never mixes with your campaign statistics. Your campaign numbers reflect real prospects only; your warmup health reflects warmup only.

What if a mailbox’s spam rate climbs — is it safe to cold-send from it?

Once about 5% of a mailbox’s warmup mail — roughly one in twenty — starts landing in spam, WarmySender automatically reduces that mailbox’s daily warmup volume to protect it, and you should get the rate well down before cold-sending from it. An elevated spam rate means too much of that mail is being filtered rather than delivered, which is a sign the reputation is not ready. Rather than pressing on, the system eases warmup back so the mailbox can recover, and picks the pace up again as placement improves. Past roughly 15%, the mailbox is also kept out of the pool that other people’s warmup is sent to.

Both of those are judged per mailbox, not per domain — a mailbox being held back does not stop your healthy mailboxes from sending, including others on the same domain.

A brand-new mailbox is not judged on a couple of emails, though: one filtered message out of two reads as 50% on paper but says nothing real. Until enough warmup mail has been placed to be confident, the mailbox keeps a small daily allowance so it can build a genuine picture instead of being held back on noise. Full explainer: why did my warmup volume go down?

Cold sending asks more of a reputation than warmup does, so a mailbox struggling to place warmup mail is not ready for cold outreach. Wait until its spam rate is back into the low single digits before you cold-send from it.

A quick operating checklist

• Authenticate your domain — SPF, DKIM and DMARC set up and passing. All three providers above require it, and it underpins everything else.
• Stay around 30–50 cold emails a day per mailbox — the default is 50, and it is a ceiling to grow into, not a target to rush to.
• Scale with mailboxes, not brute force — and remember that on a domain under 30 days old, extra mailboxes split the same 200 a day rather than adding to it.
• Leave warmup on permanently — maintenance settles around 30 a day by itself; what matters is that it never drops to zero.
• Let a new domain reach about six weeks of sending days before you treat it as fully warmed.
• Clear an elevated spam rate first — back into the low single digits before cold-sending from that mailbox.
• Keep your list clean — verify addresses before you send, and watch bounce and complaint rates.

Frequently asked questions

How many cold emails a day per mailbox is safe once warmed up?

30–50 a day per mailbox, and 50 is the default WarmySender sets. That is our recommendation, not a limit the platform enforces — your per-mailbox daily limit is settable from 1 to 500. There is no per-provider version of this number: neither Google, Microsoft nor Yahoo publishes a per-mailbox daily cold-email limit, so any “Gmail 30–50, Outlook 20–40” table is a guess. To send more, add mailboxes rather than raising one, and remember a domain under 30 days old is capped at 200 a day in total whatever you set.

Should I keep warmup running while I am cold emailing?

Yes — leave it on permanently. Reputation is a running average providers keep re-checking, so a steady trickle of genuine, wanted email holds your baseline and cushions the odd complaint from cold outreach. You do not need to pick a number: once a mailbox is established, warmup settles into maintenance around 30 emails a day on its own. Bear in mind warmup and cold share one per-mailbox daily budget, so warmup volume comes out of the same total as your campaigns.

How long until a mailbox is fully warmed?

A new domain reaches full warmup speed — 40 emails a day — around the sixth week of sending days: about 7 a day by the end of week 1, 15 by week 2, 21 by week 3, and 40 by week 6. Count sending days rather than calendar days, because warmup only advances on days the mailbox actually sends. A mailbox on an already-established domain starts higher and can reach 60. Nothing blocks you from launching a campaign sooner — we recommend waiting about three weeks of sending days, as guidance rather than a rule the product enforces.

Do Google, Microsoft or Yahoo publish a daily sending limit for cold email?

No. All three publish authentication and complaint-rate requirements, not per-mailbox volume limits. Google asks for a spam rate below 0.3% (aim under 0.10%) and applies extra requirements above 5,000 messages a day to Gmail accounts. Microsoft requires SPF, DKIM and DMARC to pass for anyone sending 5,000 or more a day to its consumer mailboxes, and refuses mail that fails. Yahoo asks for a spam rate below 0.3% and publishes no volume threshold at all. None of them publishes a day-by-day warmup schedule either — Google’s entire volume guidance is to start low and increase slowly.

Why is warmup email showing up in my inbox — will it mix with real replies?

Some warmup mail arrives in your inbox by design, because that is part of how it builds reputation. It is clearly tagged so you can recognise and filter it, and WarmySender tidies it away automatically within about a day. A message in your inbox without the warmup tag is a real person, not warmup traffic. Warmup health is measured from warmup activity separately, so it never distorts your campaign statistics.

A mailbox shows a high spam rate — can I cold-send from it?

Not yet. Once about 5% of a mailbox’s warmup mail lands in spam, WarmySender automatically eases that mailbox’s daily warmup volume back while placement recovers, and past roughly 15% it is kept out of the pool other people’s warmup is sent to. Both are judged per mailbox, so a held-back mailbox does not stop your healthy ones — including others on the same domain. Cold sending asks more of a reputation than warmup does, so wait until the rate is back into the low single digits.

Related reading

• How many cold emails can I send per day? — the canonical week-by-week table, with what the platform enforces alongside what we recommend
• Safe cold-email sending limits after warmup — the steady-state view
• How email warmup ramps up — the day-by-day curve and what changes it
• How to control your warmup sending volume — set the per-mailbox target and ramp speed
• Understanding your warmup Inbox Rate — what the number means and how to improve it
• Why warmup emails appear in your inbox — the tag and the auto-tidy, explained
• Deliverability guide — authentication, reputation and inbox placement
• Full documentation — Cold Email, Email Warmup, LinkedIn, Instagram and Multichannel guides