Verify more than one sending domain on a single MailInApp account and layer named sender identities on top of each, and one account can run campaigns as several distinct client brands — its own domain, its own from-addresses, its own tracking links, its own deliverability reputation — with no second account and no shared identity between clients.
An agency managing several clients from one MailInApp account used to have exactly one sending domain to work with, shared across every client's campaigns. Multiple sending domains and sender identities remove that ceiling: verify each client's own domain once, and everything downstream — from-address, reply-to, tracking links — can be scoped to that specific brand.
Verifying more than one domain
Settings' Sending domain card now lists every domain on the account, not just one — each verified (or in-progress) domain expands into its own detail panel with independent DNS records, verification status, from-address, and native-vs-SMTP toggle. Set default decides which domain a send falls back to when nothing more specific is configured; Disconnect removes one, refused only if an enabled recurring schedule still depends on it as its sole verified domain.
Sender identities: a name and address per brand or purpose
Once a domain is verified, a sender identity is a named {name, email, reply-to} scoped to it — [email protected] for receipts, [email protected] for newsletters, both verified by the same domain but showing recipients a different name and address. This is the same concept Brevo calls "Senders," and it's what makes multiple domains actually usable day to day instead of just theoretically possible.
Picking the right sender without choosing it every time
Four places resolve which identity — and therefore which domain — a send uses, checked in order: a schedule's own sender, a project's own sender, the audience list's default sender, and finally the account's default domain. Setting a contacts list's default sender once means every send to that client's list uses the right identity automatically, without picking it per campaign.
Branding the links, not just the from-address
A recipient who hovers a link or forwards an email to a colleague sees the link's domain too. A custom tracking domain, available on Lite and above, points live-view, click, and open-tracking links at a subdomain of the client's own domain instead of mailinapp.com — one CNAME record, automatic TLS provisioning, no certificate files to manage. Every new send from that domain uses it automatically once verified; nothing already delivered changes.
What this doesn't change
Volume metering stays account-wide, not per-domain or per-client — a pricing-axis decision, not a technical limitation, so adding a client's domain doesn't itself change your monthly send cap. Each domain's own reputation, DKIM/SPF/DMARC, and bounce/complaint handling stay fully independent of every other domain on the account, so one client's deliverability issue never touches another's.
Getting started
Verify each client's domain from Settings, create the sender identities you need on top of it, and set the right default at the list, project, or schedule level depending on how much per-send control you want. See Multiple domains & sender identities and custom tracking domain for the full setup reference, and white-label agency workflows for the template and hand-off side of running multiple clients from one account.