Deliverability briefing, Wednesday, 26 August 2026
DMARC enforcement holds at 88.4% with no new deliverability story
Nothing changed in the headlines today. Emailchaser's daily DNS check found DMARC enforcement at 88.4% across the measured panel, and Proofpoint remained the most common inbox provider at 33.7%.
Inbox Rules Index
499 of 499 companies checked, Wednesday, 26 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.
DMARC enforcement across Emailchaser's panel of 499 business domains stands at 88.4%, up 0.2 percentage points from 88.1%. This tracks the domains you send to, not customer sending data.
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.
Who changed their setup
| apollo.io | Forged mail: sent to spam → bounced | stricter |
| lloydsbank.com | Spam filter: Their own servers, or unknown → Microsoft 365 | switched |
| thermofisher.com | Sender list: no enforcement → loose list | stricter |
| walgreens.com | Spam filter: Cisco Secure Email → Mimecast | switched |
| zimmerbiomet.com | Forged mail: watched, but allowed → sent to spam | stricter |
| zoho.com | Sender list: locked list → nothing published | looser |
6 of these companies changed their email setup since Saturday, 15 August 2026: 3 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 | 33.7% | |
| 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. 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% | |
| 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.
499 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 is DMARC enforcement today?
DMARC enforcement across Emailchaser's panel of 499 business domains is 88.4% on 26 August 2026, up 0.2 percentage points from 88.1%.
What is the most common inbox provider in the panel?
Proofpoint is the most common provider, covering 33.7% of Emailchaser's measured domains, followed by Microsoft 365 at 26.1% and Google Workspace at 18.8%.
How strict is SPF across the panel?
SPF is set to strict alignment on 42.7% of measured domains, while 1.2% of domains are missing an SPF record entirely.
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