Shared Sending Infrastructure vs Per-Client Domain Isolation
IF your agency runs more than a handful of client sending domains and cannot attribute a reputation hit to a single account, THEN move to per-client domain and subdomain isolation with independent authentication before you scale volume. IF your client roster is small, contractually stable, and each account already sends under roughly 50,000 messages a month, THEN a shared pool with centralized monitoring is cheaper and faster to operate.
By InnovaAI ResearchPublished
Shared Sending Infrastructure vs Per-Client Domain Isolation
“IF your agency runs more than a handful of client sending domains and cannot attribute a reputation hit to a single account, THEN move to per-client domain and subdomain isolation with independent authentication before you scale volume. IF your client roster is small, contractually stable, and each account already sends under roughly 50,000 messages a month, THEN a shared pool with centralized monitoring is cheaper and faster to operate.”
- Two or more clients send from the same root domain, so a complaint spike on one account is indistinguishable from the others in your reporting
- A client's list source is unverified, meaning purchased, scraped, or co-registration contacts enter a domain you also use for transactional mail
- Client contracts include uptime or inbox-placement commitments that would trigger credits if a sibling account degrades shared reputation
- You already pay for authentication tooling such as EasyDMARC and can extend it per subdomain without adding headcount
- Prospects ask during procurement how their sending is separated from other agency accounts
- Every client sends under about 20,000 messages a month and none of them run cold outreach
- The agency holds fewer than five sending accounts and one person can review placement weekly
- Clients supply their own domains and DNS control, so isolation is already their responsibility, not yours
- Budget covers sending infrastructure only, with no room for per-domain warm-up or monitoring seats
- Deliverability work is billed as an ad hoc fix rather than a line item in the retainer