Hi! I was wondering if anyone else was experiencing this. We have been getting a much lower than normal open rate the past two monthly sends. We used to average between 40-50% open rate but have now dropped to 29% for each send (august & september). I first thought it was our subject line but don't think that's the cause anymore. Our delivered emails remain the same so no drop in that.
I did research on the Gmail update that happened in July that penalizes larger lists and prioritizes engagement. We do have a lot of unengaged subscribers which I am thinking could be the cause of this. Would it be worth cleaning out these subscribers to see if this fixes the issue? Any other recommendations or think this may be something else?
#Marketing Cloud #Email Deliverbility
A dropped open rate isn't primarily a Marketing Cloud automation/config issue it's a deliverability problem, and the timing lines up strongly with sending pattern, not a random content issue. A few things to check, roughly in priority order:
1. Gmail's bulk sender requirements (most likely cause) This isn't just "penalizes large lists" since Feb 2024, Gmail requires senders doing 5,000+/day to Gmail addresses to: authenticate with SPF, DKIM, and DMARC (DMARC is the one people miss), keep spam complaint rate under 0.3%, and support one-click unsubscribe (RFC 8058, List Unsubscribe header). If any of these slipped DMARC record expired, a one click unsubscribe isn't actually wired up Gmail can start routing to spam/promotions more aggressively without an outright bounce, which matches your "delivered stayed flat, opens dropped" pattern exactly (delivered ≠ inboxed).
- Check: Email Studio → Sender Authentication Package, confirm DKIM/DMARC status isn't flagged
- Check: Deliverability dashboard / Sender Reputation in Marketing Cloud for a domain/IP reputation dip coinciding with Aug/Sep
2. Engagement-based inbox placement (your instinct is right, but sequence matters)Don't just mass-suppress unengaged subscribers as a first move do it in this order:
- Pull an engagement report segmented by ISP (Gmail vs. Outlook vs. Yahoo) if the drop is Gmail specific, that confirms #1 over general list fatigue
- Check if send list composition changed recently (new list merged in, an old unengaged segment re-added) around July/August
- Then do a sunset/re-engagement flow before an outright suppression a "we miss you" send to 90+ day unengaged, suppress non-responders, rather than deleting reputation signal all at once (a sudden big list cut can itself cause a short term reputation blip)
3. Rule out the boring stuff
- Any change to send time/day between the two affected sends vs. prior months?
- Preheader/from-name change that could affect Gmail's tabbing (Promotions vs. Primary)?
- Any new links/domains in the email that could trip spam filters?
Given the pattern (delivered flat, opens down, two consecutive sends), I'd check DMARC/authentication status first that's the one thing that silently breaks and exactly matches this symptom, more so than list fatigue alone.
If you want, share your list size and roughly what % of your list is Gmail that'll tell us whether the bulk sender thresholds even apply to you.