Pre-warmed Mailboxes by EmailPal

What Does "Pre-warmed" Mean?

When you send from a new domain or mailbox, Gmail, Outlook, Yahoo and other providers do not trust it yet. If you send too many cold emails too quickly from a brand-new address, messages land in spam or the mailbox gets blocked.

Pre-warmed means the mailbox and its domain have already gone through a warm-up process, where they:

• Send gradually over time instead of jumping to campaign volume
• Hold real conversations with other inboxes to build a sending reputation
• Pass authentication checks — SPF, DKIM and DMARC
• Establish trust with major providers before you ever touch the address

In short, a pre-warmed mailbox is one a receiver has already seen behaving well, so you can start sending immediately without running the first weeks of warm-up yourself.

Age and warm-up are not the same thing. An aged domain has existed for a while; its DNS has had time to settle, but it may never have sent a message. A warmed mailbox has actually sent and received, usually starting small and increasing. A pre-warmed mailbox is a warmed mailbox you can use immediately, because that ramp already ran before the address was listed.

What Are Pre-warmed Mailboxes by EmailPal?

EmailPal pre-warmed mailboxes are leased SMTP/IMAP inboxes on domains we bought for the pool, then warmed for at least 14 days against a network of real inboxes at Gmail, Outlook and Yahoo. Every address on the shelf has a measured inbox-placement rate attached — the share of those warming messages that landed in the inbox, not a sample, not a vendor score, and not a promise.

That measurement is the product. Plenty of tools will sell you a "pre-warmed" label on an aged name. EmailPal will not list an address until:

1. We bought the domain for the pool (it is newly registered, not aged)
2. We created mailboxes and ran the standard warming ramp for at least 14 days over the public internet — never EmailPal-to-EmailPal loops
3. Real inboxes at Gmail, Outlook and Yahoo reported where each message landed
4. SPF (hard fail), dual DKIM (RSA-2048 and Ed25519) and DMARC p=reject are published and re-verified on public resolvers

When you claim a pre-warmed mailbox, you get:

• A domain we bought and authenticated for the pool
• A mailbox that already finished the standard warming ramp (at least 14 days)
• The inbox rate measured across that ramp, visible before you pay
• 15 cold emails per day recommended from the moment it is yours (the mail server allows up to 100)
• Warming that keeps running automatically, for free, for as long as you keep the lease
• Replies in the same Unibox as the rest of your account, with warming traffic filtered out by default

Leased inboxes are not counted against your plan's mailbox allowance and are not billed for warming a second time. The $3/mo lease is the mailbox, the warming and the measurement.

They are not Google Workspace or Microsoft 365 seats. They are hosted SMTP/IMAP on EmailPal infrastructure. You can send from them with EmailPal's own sequencer, Engage, paste those credentials into Instantly, Smartlead, Plusvibe or a custom sender, or send through our API.

Pricing and Availability

Pre-warmed mailboxes are available now in EmailPal.

You claim inventory by domain, so the addresses read as one company rather than a handful of unrelated names. Each listing shows:

• Domain age
• How many warming messages were measured
• Inbox-placement rate for each address
• Display names / personas already assigned (not editable)

What we check before an address is listed:

• The mailbox has warmed for at least 14 days
• The mailbox completed the standard ramp against a network of real Gmail, Outlook and Yahoo inboxes
• Placement was measured across that ramp, not estimated
• SPF (hard fail), DKIM (RSA-2048 and Ed25519) and DMARC p=reject are in place

There is no 1:3 "domain-to-mailbox ratio" you have to hit. A listed domain comes with however many mailboxes are already on it — typically a small company-shaped set. You cannot add extra handles onto a leased pre-warmed domain after the fact.

Why Use Pre-warmed Mailboxes?

Traditional mailbox setup means buying a domain, setting up mailboxes and running about two weeks of warming yourself before campaign volume is safe. Pre-warmed mailboxes skip that wait on your side. On ours, that warming is already done.

• Ready on day one — 15 cold emails per inbox, no ramp you have to run
• Placement is a number you can read before you claim, not a claim you have to trust
• Warming never stops after the lease; the $0.60/mo add-on our other customers pay is included
• No DNS work: authentication is already written and re-verified
• Outside your plan allowance, so claiming inventory does not push you into mailbox overage
• Minutes to credentials, not a 1–2 hour vendor delivery window

The honest limit: we recommend 15 cold emails per day per inbox, and that is the volume the listed inbox rate is meant to hold for. It is not a technical lock on a lease: the mail server stops any address at 100 a day, but past 15 placement falls away. If you need more volume, claim more inboxes rather than turning one address into a blast. Plan mailboxes you provision yourself also default to 15 a day per inbox, with a hard cap of 100, and they have no warming history on day one, so keep them modest until they have warmed. On domains you provision yourself, plan on 5 inboxes per domain with warming on.

How to Buy Pre-warmed Mailboxes

From the dashboard

1. Sign in to EmailPal and open Pre-warmed.
2. Each row is a domain. Expand it to see every address, display name, domain age, measured message count and inbox rate.
3. Choose Claim. A confirmation shows the monthly charge ($3 × number of inboxes on that domain), that it is month to month with no minimum term, and that nothing is billed until you confirm.
4. A job starts. Open Activity if you want to watch handover. Each mailbox's password is rotated as it becomes yours.
5. When the job completes, the addresses appear under Mailboxes. Export SMTP/IMAP from there, or GET /api/public/v1/mailboxes/export.

Notes:

• Personas (mailbox names) are assigned before the domain hits the shelf. You cannot rename them on a listed bundle.
• Passwords are never returned on the public inventory list, on purpose. They appear after the claim job.
• You do not enter a forwarding / tracking domain at checkout. Replies land in EmailPal's Unibox. If you want click-tracking links on your own domain, set up a tracking domain. If another sequencer needs a tracking domain, that is configured in that sequencer. Neither is a condition of the lease.
• Delivery is the claim job — usually minutes, not hours. Warming already ran for weeks before the address was listed.

A longer walkthrough lives in How to claim pre-warmed inboxes.

Over the API or MCP

Authenticate with an API key (Create an API key).

1. GET /api/public/v1/inventory/prewarmed lists the shelf (email, name, domain — never passwords). 2. POST /api/public/v1/inventory/prewarmed with one of: - count — take the healthiest available, up to 25 - domain_id — take the listed inboxes on one domain (preferred, keeps the company story intact) - mailbox_ids — specific IDs from the GET 3. Poll the returned job, or watch Activity.

The MCP server (npx -y @emailpal/mcp) exposes the same operations, so an agent can list and lease without a dashboard session. Set EMAILPAL_MCP_READ_ONLY=true if you only want the agent to inspect the shelf.

Sending Recommendations

To keep the reputation you paid for:

• Stay at or under 15 cold emails per day per inbox. The server will let you go up to 100, but past 15 you are spending the placement you paid for
• Do not paste identical copy across every mailbox on the domain
• Verify lists before you send; catch-alls and disabled mailboxes are why we built verification in. See How to verify an email list before sending
• Keep warming on; turning it off on a leased inbox throws away the thing the lease is for
• If a mailbox's measured placement drops, pause sending and check the warming dashboard before adding volume
• Run campaigns in EmailPal's own sequencer, Engage, or connect the mailboxes to another sequencer over SMTP/IMAP. EmailPal does not provide a dialer

Unlike a fresh mailbox, you do not start at 20–30/day and add five a day. The ramp already happened. Staying near 15/day is how you keep that measurement from collapsing the first week you use the address.

Pre-warmed vs warming a mailbox you own

If you can wait, register or bring a domain and turn on Email warming by EmailPal. If you need to send this week, lease inventory. They are different SKUs; warming a plan mailbox does not convert it into a pre-warmed listing.

Aged, unwarmed domains (from $19) are a third path: parked 60+ days, still not pre-warmed. You run the accelerated ramp yourself (about a week to the ceiling).

FAQs

What is a pre-warmed mailbox?

A mailbox that has already finished a warm-up ramp against real provider accounts, so you can send cold email immediately. On EmailPal that ramp is measured: you see the inbox-placement rate before you claim.

Are the domains generic or custom?

They are domains EmailPal bought for the pool and warmed. You do not bring your own domain for this product — that is a separate path under Domains and mailboxes. You also do not pick custom mailbox names on a listed bundle; personas are already assigned.

How many mailboxes come with a domain?

Whatever is listed on that domain's row. You claim the domain as a set so the addresses look like one company. There is no "add a fourth mailbox later" on a leased pre-warmed domain.

How long until I can send?

As soon as the claim job finishes and credentials have rotated — usually minutes, not hours. Warming already ran for weeks before the address was listed.

Can I add more mailboxes to a leased pre-warmed domain later?

No. Additional mailboxes on that domain are not part of the lease. Register or bring a domain of your own if you want to provision more senders.

Are passwords provided?

Yes. After the claim job, export credentials from Mailboxes or GET /api/public/v1/mailboxes/export. Passwords are never returned on the public inventory list.

How is deliverability ensured?

Each inbox is warmed against a network of real Gmail, Outlook and Yahoo inboxes. Those accounts report where the mail landed. The inbox rate on the listing is that measurement. Authentication is SPF, dual DKIM and DMARC p=reject. Warming stays on after you claim. We do not sell a separate "inbox placement test" SKU — the listing *is* the test.

How does billing work, and what happens if I release an inbox?

$3 per inbox per month, billed monthly from the day you claim it, with no minimum term. You can release an inbox at any time: releasing hands the address back to the pool and stops future monthly charges. The month already billed is not prorated or refunded. See Pre-warmed billing and releasing an inbox.

Can I use these with Engage, Instantly, Smartlead or another sequencer?

Yes. Pick them in an Engage campaign once they show as ready, or export SMTP and IMAP and add them as sending accounts in another tool. See SMTP vs Google vs Outlook for cold email.

Are these Google or Outlook accounts with admin access?

No. If you need a Workspace or Microsoft tenant, you are shopping a different vendor. EmailPal-hosted mailboxes avoid phone-verification loops and shared-tenant Outlook rejections; they also will not give you a Google admin console.

Why do you recommend only 15 emails a day if the mailbox is already warm?

Receivers still watch new campaign patterns. Fifteen a day is the volume we recommend, so the measured inbox rate stays a description of how you send rather than a memory of warming. The mail server allows up to 100 a day on any address, but placement drops well before that.

What if the shelf is empty?

Inventory lists itself when pool inboxes finish warming. Check back, provision your own domains, or look at aged, unwarmed domains. There is no free trial of the shelf.

Who can I contact for help?

If you have an account, open a support ticket. If you are still evaluating, the same facts are on the pre-warmed product page.

Need More Help?

Questions about claiming, credentials or sending limits: open a ticket from your account, or read How to claim pre-warmed inboxes and Email warming by EmailPal.