Deliverability briefing, Friday, 28 August 2026
Most Of The Companies You Email Sit Behind Proofpoint Or Microsoft
No new deliverability story cleared two outlets today, so the numbers carry the news. Emailchaser's daily check of business domains found the mix of mail gateways sitting in front of them barely moved, with Proofpoint and Microsoft 365 still the two most common filters reading mail before it reaches an inbox.
Inbox Rules Index
499 of 499 companies checked, Friday, 28 August 2026
Every morning we look up the published email settings of the same 499 real companies, the kind you send cold email to. This is what they have set up, not a score on your own sending.
Today's check found 88.4% of the 499 companies in Emailchaser's panel block mail that fakes their own address, unchanged from 26 August 2026 and up 0.6 percentage points from the 10 August 2026 baseline. That is a sign of how seriously these companies run their own email security. It says nothing about how your cold email will be treated, because that depends on your own domain's settings, not theirs.
What this means for your sending
Proofpoint screens more of these companies than anything else, at 33.7%, so it is the filter most of your cold email actually meets. 6.2% ask senders for an encrypted connection, so an expired or mismatched certificate on your sending server can stop mail reaching them at all. 2.4% cannot receive email at all, which is dead weight on any list that includes them. The rest is about how these companies stop others forging their address. It is a good sign of how seriously they run email security, but it is not what decides where your mail lands: that is judged against your own domain's records.
Whose spam filter your email meets
| Proofpoint | 33.7% | |
| Microsoft 365 | 26.1% | |
| Google Workspace | 18.8% | |
| Their own servers, or unknown | 9.8% | |
| Mimecast | 4% | |
| Cisco Secure Email | 3.8% |
Proofpoint screens about one in every 3 of these companies, more than any other filter. This is the software that reads your email before a person does, and it is the part of this briefing that most directly decides whether you land.
Which industries guard their name hardest (companies checked)
| Software (126) | 97.6% | |
| Finance (54) | 94.4% | |
| Services (28) | 92.9% | |
| Healthcare (47) | 89.4% | |
| Logistics (17) | 88.2% | |
| Retail (50) | 88% | |
| Travel (25) | 88% | |
| Energy (24) | 87.5% | |
| Media (26) | 84.6% | |
| Telecoms (30) | 80% | |
| Industrial (44) | 79.5% | |
| Schools and universities (28) | 57.1% |
Software guards its name hardest: 97.6% block mail faking their address. Schools and universities least, at 57.1%, a gap of 40.5 points. A high number means that industry runs email security tightly, so expect your own setup to be looked at more closely there.
All 499 of the 499 companies we check answered today. The same real companies every morning, looked up in public DNS. This is what the people you email have set up, not a score on your own sending.
What these numbers mean
Does DMARC enforcement mean my cold email will be blocked?
No. DMARC enforcement, at 88.4% across the panel, shows a company blocks mail that fakes its own address. It says nothing about how your cold email is judged, because that is decided by your own domain's settings, not the recipient's.
What gateway will my cold email actually pass through?
Most likely Proofpoint or Microsoft 365. Proofpoint sits in front of 33.7% of the companies in the panel, Microsoft 365 in front of 26.1%, and Google Workspace behind 18.8%. Each gateway reads and filters the message before it ever reaches an inbox.
Has anything changed since yesterday's check?
No. DMARC enforcement held at 88.4%, unchanged from 26 August 2026, and up 0.6 percentage points from the 10 August 2026 baseline.
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