Deliverability briefing, Saturday, 15 August 2026
No deliverability stories today: DMARC enforcement climbs to 88.1%
There is no new deliverability story today. Instead, the news is in the numbers. DMARC enforcement across Emailchaser's panel of 499 business domains rose to 88.1%, up 0.4 percentage points from 87.9% on 10 August 2026.
Inbox Rules Index
497 of 499 companies checked, Saturday, 15 August 2026
On each measurement 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.
Emailchaser measured 497 of 499 panel domains today. DMARC enforcement reached 88.1%, up 0.4 percentage points from 87.9% on 10 August 2026. Strict SPF sits at 42.9% and MTA-STS at 4.8%, both still minority practices. This is a measurement of the domains you send to, not a report on your own sending.
What this means for your sending
Proofpoint screens more of these companies than anything else, at 33.8%, so it is the filter most of your cold email actually meets. 4.8% 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.
Who changed their setup
| duke-energy.com | Forged mail: watched, but allowed → sent to spam | stricter |
| riteaid.com | Forged mail: watched, but allowed → sent to spam | stricter |
| thermofisher.com | Spam filter: Proofpoint → Their own servers, or unknown | switched |
| tractorsupply.com | Sender list: locked list → loose list | looser |
4 of these companies changed their email setup since Monday, 10 August 2026: 2 got stricter, 1 got looser. If any are on your list, the stricter ones are running their email security actively.
Whose spam filter your email meets
| Proofpoint | 33.8% | |
| Microsoft 365 | 25.8% | |
| Google Workspace | 18.9% | |
| Their own servers, or unknown | 10.1% | |
| Cisco Secure Email | 3.8% | |
| Mimecast | 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. It says nothing about how any one of them treats your mail.
Which industries guard their name hardest (companies checked)
| Software (126) | 97.6% | |
| Finance (54) | 94.4% | |
| Services (28) | 92.9% | |
| Logistics (17) | 88.2% | |
| Retail (50) | 88% | |
| Travel (25) | 88% | |
| Energy (24) | 87.5% | |
| Healthcare (45) | 86.7% | |
| 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.
497 of the 499 companies we check answered on this measurement. A fixed panel of real business domains, measured every day over public DNS. This is a measurement of the domains a sender emails, not of Emailchaser customer sending data.
What these numbers mean
What percentage of domains enforce DMARC today?
88.1% of the 497 measured domains enforce DMARC with a policy of quarantine or reject, up from 87.9% on 10 August 2026, a rise of 0.4 percentage points.
What is the weakest sector for DMARC enforcement today?
Education, at 57.1% enforcement across 28 measured domains. Every other sector measured sits at 79.5% or higher, with SaaS the strongest at 97.6% across 126 domains.
Did any domain change its DMARC policy today?
Yes. duke-energy.com and riteaid.com both moved from no policy to quarantine. tractorsupply.com's SPF policy loosened from strict to soft, a step in the wrong direction.
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