Your sender reputation isn't dead — it's recoverable. Here's what to do this week:
Move 1: Scrub your list until bounce rates drop below 2%
Per Apollo.io, a paid data provider, a reasonable benchmark for email bounce rates is under 2% total, with hard bounces ideally below 1%. Start by removing all hard bounces immediately — sending to them again flags you as a spammer. Then suppress contacts who haven't engaged recently so you're only mailing people who actually want to hear from you.
One outbound prospecting agency, cited in a vendor-affiliated LinkedIn post, reported that after switching to verified list data for cold outreach, their bounce rate dropped to under 2%, reply rates doubled, and sender score recovered in two weeks. That's a single anecdote from a commercial source, so treat it as directional — but the underlying principle (clean data = faster recovery) is consistent across every deliverability resource out there. Note that this example comes from a cold outbound context; if you're recovering from a marketing campaign, the same list hygiene logic applies, though your re-engagement window will differ.
This is the single fastest way to signal to ISPs that you're serious about sending clean mail.
Move 2: Cut volume and target only your most engaged contacts
Switch to sending only to your most engaged segment — people who opened or replied recently. Dramatically reduce your sending volume while you stabilize. SMTP.com supports gradual volume reduction as the most important recovery strategy, noting that sudden volume spikes can trigger additional ISP scrutiny, while gradual, steady sending builds trust.
Domain reputation — which follows you across ESPs and infrastructure changes — takes considerably longer to repair than IP reputation, according to Prospeo, an email data vendor. SMTP.com puts the overall recovery window at 4–12 weeks for most organizations, with severely damaged reputations potentially requiring 3–6 months of consistent effort. Organizations with minor issues may see improvement sooner. There's no shortcut around this timeline, but focusing on engaged recipients generates the positive engagement signals (opens, replies, clicks) that accelerate it.
Keep your spam complaint rate below 0.1% (that's 1 in 1,000 messages sent) — that's the enforcement threshold HubSpot applies on its own platform, and it aligns with the sender guidelines major inbox providers have adopted industry-wide. SMTP.com independently cites keeping spam complaints below 0.1% as a key benchmark for maintaining good sender reputation during recovery.
Don't try to "make up" for lost volume by blasting your full list. That backfires. Steady, clean sending wins.
Also: make sure your authentication is airtight
While you're cleaning house, verify that SPF, DKIM, and DMARC are correctly configured. SMTP.com explicitly calls out proper authentication as something that accelerates the recovery process — ISPs use it to confirm you're a legitimate sender, and missing or misconfigured records will slow you down regardless of how clean your list is.