Run outbound for every client from one place. Give each client its own domains, keep them apart with tags, change hundreds of domains in one action, and hand each client's mailboxes to whichever sequencer that client uses.
An agency's infrastructure problem is not one big campaign. It is fifteen small ones that must never touch each other. Each client needs its own sending domains, so a list problem or a complaint spike on one client's campaign cannot damage another client's reputation. Each client's domains should redirect to that client's website, forward replies to an inbox the client or your team watches, and plug into the sequencer that client's campaign runs in.
Then there is the churn: onboarding a client means buying and warming dozens of domains at once, and losing one means retiring them just as cleanly. Doing that one domain at a time does not scale past a handful of clients. Winnr is built around bulk: buy many domains in one order, select by tag, and apply the same change to everything selected.
Buy a client's domains in one order with that client's website as the redirect and a forwarding address for replies. If the client already owns domains, connect them for free, whatever registrar they use.
Tag domains by client (client-acme) and by campaign or age. Add tags in the purchase wizard or in bulk later. Tags become filters on the Domains and Warming pages, so one click shows one client.
Filter by a client's tag, tick the header checkbox, and act on just those domains: tags, redirect, forwarding, custom DNS records and DMARC, add mailboxes, enable warming, or delete. Large deletes are split into batches of 100 for you.
The Warming page's tag filter shows the mailboxes on one client's domains, with each mailbox's 0 to 100 health score, so you can see whose setup needs attention.
Tick a client's mailboxes on Email Users, or call the export endpoint with that client's domain list, and download the file in the format of the sequencer that client uses.
Save a set of up to 10 sender names as a mailbox template and apply it when you add mailboxes to a new client's domains, instead of typing the names again.
client-acme, and enter the client's website as the redirect and an inbox for forwarding.Reference: domain tags, bulk operations and mailbox templates.
Everything above can run without the dashboard. The REST API at api.winnr.app/v1 covers buying and connecting domains, creating mailboxes, DNS records, warming, the inbox, exports, pre-warmed purchases and webhooks, with Bearer tokens you create in the app. Startup gets 300 requests a minute and Enterprise 500, and the OpenAPI spec is at app.winnr.app/docs. A worked example: buy domains, provision inboxes and export them for Instantly through the API.
The hosted MCP server gives Claude, ChatGPT, Cursor and other assistants the same operations in plain language, and Claude Code skills package common workflows such as setup, scaling and health checks. Inside the app, the Winnr Agent can change DNS records or DMARC on up to 50 domains per request and shows you the change before anything happens.
For reporting, webhooks send signed events to your own systems, and the universal mailbox shows replies from every mailbox in one feed with a filter by mailbox, with warmup mail hidden.
Some agencies do not want clients to see which infrastructure provider they use. On request, Winnr will set up a dedicated mail server on a hostname you control. The SMTP and IMAP endpoints your clients' tools connect to are then branded as yours. Pair that with sending domains registered in each client's own name and connected to Winnr, and nothing a client sees points back to Winnr. Email support@winnr.app to arrange it.
If you want your account's sending isolated from Winnr's shared pools, dedicated IPs are available on the Enterprise plan at $20 per IP per month, set up by the support team. Most senders do well on the shared pools; see dedicated IPs.
Plan prices divided out. Sequencer subscriptions are separate.
| 200 mailboxes | 1,000 mailboxes | |
|---|---|---|
| Plan | Enterprise, $189/month | Enterprise + 800 extra mailboxes at $1 = $989/month |
| Warming on every mailbox ($0.60 each) | +$120, so $309/month | +$600, so $1,589/month |
| Domains at 5 mailboxes each | 40, which fits Enterprise's default 40 slots | 200; raise slots 40 to 80 to 160 to 320, one free doubling per 24 hours |
| Domain purchases, one-time | About $455 at about $13 per .com after 5 free; $0 for client-owned domains | About $2,535 after 5 free; $0 for client-owned domains |
| Cold emails a day at 15 per mailbox | 3,000 | 15,000 |
| Per mailbox, plan plus warming | $1.55/month | $1.59/month |
Ten clients with 100 mailboxes each is the 1,000 column: about $98.90 per client per month for the plan, or $158.90 with warming on every mailbox. Without warming, or with clients' own domains, the totals drop accordingly. The same 1,000 mailboxes as Google Workspace Business Starter seats would list at $7,000 a month on an annual plan as of October 2026; see the Google Workspace comparison. Size your own setup with the cold email calculator.
Clients rarely agree on a sending tool. Winnr exports mailboxes in 21 tool-specific formats plus a generic CSV, so each client's file matches what that client's sequencer expects. Exports are free. Format details for the three agencies ask about most: Smartlead, Instantly and EmailBison. The full list is in the integration guides.
Whatever the tool, keep cold sending at 10 to 20 emails per mailbox per day, and each mailbox's total, cold plus warming, at 50 or under. Add clients' volume by adding mailboxes and domains, not by pushing each mailbox harder.
No annual contract. Cancel anytime.
50 email accounts and 10 domain slots.
Everything in Startup, at four times the scale.
Extra email accounts are $1/month each on either plan. Warming is $0.60/mailbox/month. Full pricing.
Enterprise is $189/month for 200 mailboxes, and extra mailboxes are $1 each. Billed monthly, cancel anytime.
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