A 90-Day Deliverability Runbook for a New Portco Operator

Bolt-on acquisitions almost always leave behind sending domains nobody fully owns anymore, old brand names, acquired-company domains still technically active, and shadow IT accounts set up by a departed sales leader who never documented what they'd built. List every domain currently sending mail on the company's behalf, and check basic authentication, SPF, DKIM, DMARC, on each one, since a domain missing any of these is already starting from a real deliverability deficit before you've even sent your first message from it as the new operating team.

Run a placement check against the domains carrying the most volume or the most valuable relationships, rather than trying to audit everything with equal priority in the first month, when time and attention are both in short supply. Mailreach's continuous, provider-by-provider checking gives a clear before picture worth having, both for prioritizing the rest of the ninety-day plan and for showing the board a concrete before-and-after comparison once the work is actually done and the numbers have had time to settle.

Not every legacy domain needs to disappear immediately, but each one needs a clear decision made about it: consolidate onto the primary sending identity, or keep it deliberately separate for a specific purpose with its own monitoring plan attached to it. What shouldn't continue is three domains sending overlapping mail with nobody accountable for any of their reputations, which is the default state most bolt-on integrations land in without anyone actually deciding it on purpose at any point along the way.

If the placement baseline from day 30 showed a domain carrying active deal flow is already filtered at meaningful providers, bring in InboxAlly to actively rebuild it rather than waiting for a broader consolidation project to resolve the issue naturally over several quarters of gradual improvement. Mailreach is cheap enough to run across a messy multi-domain estate while you sort it out; InboxAlly is worth the more targeted spend specifically on the one domain carrying revenue-relevant conversations right now, during the window the board is watching most closely.

Tie the deliverability work back to reply rates and pipeline velocity rather than presenting it as an infrastructure project sitting on its own separate slide nobody engages with. A clean domain inventory and confirmed placement across the providers your buyers use is a concrete input into the broader commercial diligence story you're building for the next board meeting, not just a technical cleanup item buried in an appendix nobody actually reads before walking into the room to present it.

Across all industries, the open rate Mailchimp tracks averages 35.63 percent¹. Outbound from a consolidated, properly authenticated domain should clear that baseline comfortably across every major provider your buyers actually use, not just the one or two you happened to check first when the project started. A portfolio company still tracking near the all-industry average ninety days into a deliverability cleanup has more domain consolidation work left to do, not a content or targeting problem it should be chasing down instead.

Once the ninety-day cleanup is done, write down the checklist so the next bolt-on doesn't recreate the same mess from scratch: inventory sending domains within the first two weeks of close, check authentication immediately, and decide on consolidation before the acquired team's old habits calcify into permanent shadow infrastructure nobody remembers approving months later. A playbook that takes an afternoon to write saves weeks of untangling on every future deal the platform does, and it gives the next operating partner a running start instead of a blank page and a mystery to unravel from scratch.

Write the checklist down for the next add-on acquisition:

1. Inventory every sending domain within the first two weeks of close, including old brand names and accounts a departed sales leader set up.
2. Check SPF, DKIM, and DMARC authentication on each domain immediately, since a missing check is already a deliverability deficit.
3. Decide whether each legacy domain consolidates onto the primary identity or stays separate with its own monitoring plan.
4. Run a placement baseline on the domains carrying the most volume or the most valuable relationships first.
5. Report the result to the board in terms of reply rates and pipeline velocity, not as a standalone infrastructure project.