Cold email inboxes
for Smartlead

Winnr supplies the domains and SMTP/IMAP mailboxes; Smartlead runs the campaigns. Export your mailboxes in Smartlead's format, bulk-upload the file, set the daily limit, and start sending once they are warm.

Get started See the CSV columns

50 mailboxes for $69/mo Smartlead export built in SPF, DKIM, DMARC automatic Built-in warming $0.60

By the Winnr Deliverability Team · Updated Oct 6, 2026

How it fits

Smartlead sends. Winnr is what it sends through.

Smartlead is a sequencer: campaigns, rotation across mailboxes, a master inbox and its own warmup. It does not come with mailboxes. As of October 2026, every Smartlead plan includes unlimited email accounts at no extra cost, so the Smartlead bill grows with the emails you send and the contacts you store, not with how many mailboxes you connect. That makes cheap, plentiful mailboxes the natural pairing.

Winnr provides them. You buy domains in Winnr (a .com is about $13, one-time) or connect your own, and Winnr publishes SPF, DKIM and DMARC and creates the mailboxes. Each one is a standard SMTP and IMAP account: SMTP on port 465 and IMAP on port 993, both SSL, with the full address as the login. Smartlead sends through Winnr's SMTP host and reads replies over IMAP, so its master inbox works as usual, and Winnr's universal mailbox shows the same replies if your team prefers it.

The export

The Smartlead file, column by column

Generated by Winnr's export, so every row matches what Smartlead's SMTP upload expects.

Column	What Winnr puts in it	Used for
`domain`	The mailbox's domain	Reference only; can be skipped
`from_email`	The full email address	Sender address
`from_name`	The mailbox's display name	Sender name
`user_name`	The full email address	SMTP login
`password`	The mailbox password	SMTP password
`smtp_host`	That mailbox's mail server	SMTP server
`smtp_port`	465 (SSL)	SMTP port
`imap_host`	That mailbox's mail server	IMAP server
`imap_port`	993 (SSL)	IMAP port
`imap_username`	The full email address	IMAP login
`imap_password`	The mailbox password (same as password)	IMAP password
`footer`	The mailbox's footer, usually empty	Email signature, if you use one

The Smartlead format has exactly the same 12 columns, in the same order, as Winnr's Default export. There is no daily-limit or warmup column, so Smartlead applies its own defaults on import and you change them afterwards. Mailboxes on different domains can sit on different mail servers, so keep each row's own hosts. Only mailboxes that have finished being created are exported.

Import

From Winnr to a connected Smartlead account

Select the mailboxes. On Winnr's Email Users page, tick the mailboxes for this campaign. Filter by a domain and tick the header checkbox to take all of its mailboxes. With nothing ticked, the export includes every mailbox in the account.
Export in the Smartlead format. Click Export, choose Smartlead under Export Format, click Export, then Download CSV. The link lasts 15 minutes, and the file holds passwords in plain text, so keep it private.
Upload to Smartlead. In Smartlead, open Email Accounts, add accounts and choose the bulk CSV upload for SMTP/IMAP accounts. If it asks you to map columns, use the table above.
Set the daily limit and warmup. Change each mailbox's limit to 15 cold emails a day and decide which tool warms it (below).
Confirm every mailbox connected. Check each account shows as connected before you add it to a campaign. Adding more later? Export only the new mailboxes so Smartlead does not see duplicates.

Step-by-step with screenshots: Connect Winnr mailboxes to Smartlead.

Settings

The two settings to change after upload

Daily limit: 15 cold emails per mailbox

Because the file carries no limit, set it in Smartlead: 10 to 20 cold emails per mailbox per day, 15 as the default. Each Winnr mailbox should send about 50 emails a day or fewer in total, and that total includes warming, so 15 cold leaves room for up to 35 warmup emails. Warm new mailboxes for at least two weeks before they send cold, and longer on a brand-new domain. More volume should come from more mailboxes, which cost Smartlead nothing extra to connect.

Warmup: Winnr's or Smartlead's, never both

	Winnr warming	Smartlead warmup
Cost	$0.60 per mailbox per month	Part of your Smartlead plan
Where you switch it on	Winnr Warming page, or Enable Warmup on selected domains	Each email account's warmup setting in Smartlead
What you see	A 0 to 100 health score and inbox-rate charts per mailbox	Smartlead's own warmup stats
Keeps working if you change sequencer	Yes, it lives with the mailbox	No, it lives in Smartlead

Pick one per mailbox. A mailbox warmed by both is warmed twice and pushed past 50 emails a day. More on how Winnr's warming works: email warming.

Cost

What Smartlead plus Winnr costs per month

Smartlead plans include unlimited email accounts, so its cost follows sends, not mailboxes.

Mailboxes	Cold emails a month at 15 a day	Smartlead plan that covers it	Winnr	Total
50	22,500	Pro, $94 (90,000 sends)	$69 (Startup)	$163
200	90,000	Pro, $94 (90,000 sends)	$189 (Enterprise)	$283
300	135,000	Unlimited Smart, $174 (150,000 sends)	$289 (Enterprise + 100)	$463
1,000	450,000	Unlimited Prime, $379 (500,000 sends)	$989 (Enterprise + 800)	$1,368

Smartlead prices from smartlead.ai/pricing, monthly billing, checked October 6, 2026; yearly billing is about 17% less. Smartlead's Base plan ($39, 6,000 sends a month) covers about 13 mailboxes at 15 a day. Monthly figures assume 30 days of sending; follow-ups count toward each mailbox's 15. Winnr warming adds $0.60 per mailbox and domains are a one-time purchase. Smartlead also sells mailboxes through its SmartSenders add-on, from $3.99 per SMTP mailbox per month on the same page; we compare the two in SmartSenders alternative.

Troubleshooting

If a mailbox will not connect in Smartlead

Wrong password. A password changed in Winnr after the export will not match the file. Export that mailbox again and re-upload it.
Columns mapped crosswise. If Smartlead asked you to map fields, check that user_name and password went to SMTP and imap_username and imap_password went to IMAP.
Edited hosts. Do not replace a row's smtp_host or imap_host with another row's; mailboxes on different domains can use different servers.
Still failing on a fresh export? Follow fix a mailbox that will not connect.

Mail Smartlead sends goes out through the Winnr SMTP host in the file, exactly like any other mail from your Winnr mailboxes, including through a dedicated IP if your Enterprise account has one.

FAQ

Winnr and Smartlead: common questions

Is Winnr's Smartlead export different from the Default export?

No. Both have the same 12 columns in the same order: domain, from_email, from_name, user_name, password, smtp_host, smtp_port, imap_host, imap_port, imap_username, imap_password and footer. Choosing Smartlead just makes the file easy to recognise later.

What daily limit should I set for Winnr mailboxes in Smartlead?

10 to 20 cold emails per mailbox per day, with 15 as a good default. Keep each mailbox's total, cold plus warming, at 50 or under, and add mailboxes rather than raising the limit when you need more volume.

Should I use Smartlead's warmup or Winnr's warming?

Pick one per mailbox. Winnr's warming is $0.60 per mailbox per month and stays with the mailbox if you change sequencer; Smartlead's warmup is part of your Smartlead plan. If Winnr warms a mailbox, turn Smartlead's warmup off for it.

Does Smartlead charge per mailbox?

As of October 2026, Smartlead's pricing page says all plans include unlimited email accounts at no extra cost. Its plans are priced by emails sent and contacts stored, so connecting more Winnr mailboxes does not raise the Smartlead bill.

How do I add new Winnr mailboxes to Smartlead later?

Tick only the new mailboxes on Winnr's Email Users page, export them in the Smartlead format and upload that file. Smartlead then gets the new accounts without duplicates of the ones it already has.