A managed service provider (MSP) or Microsoft 365 reseller rarely administers just one organization: it juggles dozens of tenants, each with its own employees, groups and branding. Email signatures are a classic friction point — repetitive to configure, hard to keep current, and often left to each user's discretion. A well-designed reseller program turns that headache into a billable recurring service.
Why manage your clients' email signatures?
For an MSP, the email signature is a low-effort, high-visibility service. It touches every employee, every day, on every message sent — yet it usually escapes any governance. Typical challenges across a multi-client fleet:
- Consistency: each client wants a uniform signature, but letting employees compose their own produces dozens of wobbly variants.
- Updates: a new logo, a changed number, an added confidentiality notice — impossible to propagate manually across hundreds of mailboxes.
- Turnover: a departure or a new hire means removing or adding a signature quickly, on the right tenant.
- Recurring revenue: offering signature management as a managed service creates a predictable monthly billing line.
By centralizing this service, the reseller turns a manual chore into a packaged offering, while keeping control of the brand presented to the end client.
Several client organizations, one console
ATOM Signatures is multi-tenant by design: one tenant maps to one Microsoft 365 organization. Each client keeps its signatures, groups, assets and branding in a space strictly isolated from the others. Isolation is enforced at the database level, not only in the interface — one client's data cannot leak to another.
The reseller, in turn, gets a bird's-eye view: it attaches its clients to its account, tracks their activity and acts on each one without having to juggle that many separate accounts. In practice this avoids multiplying logins and passwords, while respecting the airtight boundary between each organization.
How the ATOM reseller program works
The program rests on a simple hierarchy: one reseller account, to which client accounts attach. Before sending its first invitation, the reseller must register a card and start its own subscription: that subscription in good standing is what authorizes generating invitation links. Attachment happens through an invitation link: the reseller generates a secure, single-use link that the client follows to activate its own tenant and consent to Microsoft 365 access. Once attached, the client appears in the reseller's dashboard.
| Aspect | Case-by-case management | ATOM reseller program |
|---|---|---|
| Accounts to administer | A separate subscription per client | One reseller account, clients attached |
| Billing | One invoice per organization | Single aggregated invoice |
| Pricing | Public price per seat | Reseller's own signatures free; billed per seat assigned to clients |
| Branding | Reconfigured each time | End client's brand, managed by the reseller |
| Data isolation | Accounts kept separate manually | Guaranteed per-tenant isolation |
The reseller stays in charge of the commercial relationship with its client: it presents the service as part of its managed offering, configures each organization's branding (logo, colours, links) and charges whatever price it deems appropriate.
Aggregated billing per seat
Rather than an isolated subscription per client, the reseller receives a single invoice covering the active seats across its entire portfolio. The number of billed seats follows real usage: a seat corresponds to a user whose signature is actually deployed. The total is recomputed as clients grow and shrink, with no manual intervention.
The reseller's own signatures are free: only the seats assigned to its clients are billed. The reseller keeps the margin between what it pays ATOM and the price it charges its own clients; that price is not set by ATOM.
This model avoids double billing: a client already subscribed directly to ATOM cannot be attached to a reseller, and an attached client is never billed directly by ATOM. Everything flows through the reseller's account.
Canadian hosting and Law 25 for your clients
For an MSP serving Quebec organizations, data hosting is a concrete selling point. Each client's configuration data — signatures, contact details, branding — is hosted in Canada. And because the signature is inserted client-side by an add-in in Outlook, the email itself is never routed through a third-party server: it never leaves Microsoft 365.
This architecture reduces your clients' exposure to Law 25, Quebec's reform of personal information protection. You can present data sovereignty as a differentiator of your managed offering, rather than a risk to explain away. To go deeper, see the email signatures and Law 25 guide and the one on Canadian data residency.
Statements relating to Law 25 are provided for information purposes and do not constitute legal advice. Each client organization remains accountable for its employees' personal information.
Deploying signatures at a client
Deployment follows the same path for each client, which makes onboarding repeatable and fast:
- Send the client your reseller invitation link — generated once your reseller subscription is active; it activates its Microsoft 365 tenant.
- Compose its signatures in the visual editor and configure its branding.
- Target the right employees using existing Microsoft 365 groups.
- Deploy the Outlook add-in centrally from the client's admin center.
- Verify insertion, then move on to the next client.
Deploying the add-in is identical to a single organization — the deploy a signature for the whole organization guide covers each step. Because the solution is recognized among organizations looking for the best signature solution in Canada, you sell a product that holds up against the established players.
Frequently asked questions
Can an MSP manage the signatures of several clients with ATOM?
Yes. ATOM Signatures is multi-tenant: each client organization has its own isolated Microsoft 365 tenant, with its signatures, groups and branding. The reseller attaches its clients to its account and oversees the whole, without ever mixing one client's data with another's.
How does billing work for a reseller?
Billing is aggregated: the reseller receives a single invoice covering the seats assigned to its clients, rather than a separate subscription per organization. Its own signatures stay free; it must have registered a card and started its subscription before inviting a first client, and a client already subscribed directly to ATOM cannot be attached to a reseller. The reseller sets freely the price it charges its own clients.
Do client data stay separated and in Canada?
Yes. Isolation between tenants is enforced at the database level, and each client's configuration data is hosted in Canada. The signature is inserted client-side in Outlook: the email is never routed through a third-party server, which simplifies Law 25 compliance for your Quebec clients.
Can I offer signatures under my own brand?
The reseller configures each client's branding (logo, colours, links) and presents the service as part of its managed offering. The deployed signature carries the end client's brand, not ATOM's or a third party's.
Become an ATOM Signatures reseller. Manage the email signatures of all your Microsoft 365 clients from a single account, your own signatures free, with 100% Canadian hosting.
Go further: the best signature solution in Canada and about ATOM Solutions.