Why are my emails going to spam?
Almost always authentication first, reputation second, content third, in that order. On 2026-09-05, 88.4% of the 499 business domains measured enforce DMARC, and 70.3% of all measured domains are at p=reject. Enforcement is rising: up 0.4 points over the last 9 measurements. That is more of the companies you email locking down their own name, which tracks how seriously they run email security. It does not mean they reject your mail: yours is judged against your own records. About 42.9% of the business domains a cold emailer targets route inbound mail through a security gateway, Proofpoint alone 33.9%, measured 2026-09-05.
Check authentication before you touch a single word of copy
Rewriting subject lines is the most common first move and the least likely to fix anything. If SPF, DKIM and DMARC alignment are not right, no amount of copy editing changes the outcome, because the message is being judged before the content is read.
Three things have to be true on your sending domain: SPF authorises the servers you actually send from, DKIM signs with a key published under the sending domain, and DMARC alignment passes so the domain in your From address matches the one that authenticated. 43.1% of the domains measured on 2026-09-05 go as far as a strict SPF policy on their own mail, which tells you how normal this has become.
On 2026-09-05, 1.2% of measured domains publish no DMARC record at all. That is the group where an unauthenticated message might still land, and it is exactly why intermittent delivery is so confusing to diagnose: the same broken setup succeeds against some recipients and fails against others.
Then reputation: volume, complaints and bounces
Mailbox providers score the sending domain and IP over time. A new domain sending a thousand messages on day one looks like exactly the thing spam filters exist to stop, whatever the content says. Ramp volume, keep the complaint rate low, and keep bounces low by verifying addresses before you send.
Bounces are the fastest way to lose a domain's reputation, and they are the easiest to prevent. A list that has not been verified will contain dead addresses and spam traps, and both are read as a signal that you did not get permission for the list.
Who is actually filtering your mail
Across the panel measured on 2026-09-05, inbound mail is received by Proofpoint 33.9%, Microsoft 365 26.1%, Google Workspace 18.8%. 42.9% of the 499 domains sit behind a security gateway of some kind, and a gateway in front of Microsoft 365 or Google Workspace is counted as the gateway because it is the software that reads the message first. A gateway applies its own rules on top of the mailbox provider's. This is what the recipients have set up, not a prediction of where your mail lands.
MTA-STS is the other signal worth watching: 6.4% of measured domains publish it, which requires your outbound connection to use valid TLS to reach them. The full Inbox Rules Index below shows the provider mix and the sector split, 10 measurements since 2026-08-10.
Content, last
Content matters least and gets the most attention. Once authentication and reputation are right, the things that still hurt are large images with almost no text, link shorteners, too many links, and a missing unsubscribe mechanism. A list-unsubscribe header is a requirement for bulk senders now, not a nicety.
Inbox Rules Index
Measured Saturday, 5 September 2026 across 499 real business domains, 10 measurements since 2026-08-10. 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. It does not predict where your mail lands: that is judged against your own domain's records.
Whose spam filter your email meets
| Proofpoint | 33.9% | |
| Microsoft 365 | 26.1% | |
| Google Workspace | 18.8% | |
| Their own servers, or unknown | 9.6% | |
| 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.
The last 10 measurements
| Date | DMARC enforced | At p=reject | No DMARC | Strict SPF | Domains measured |
|---|---|---|---|---|---|
| 2026-09-05 | 88.4% | 70.3% | 1.2% | 43.1% | 499 |
| 2026-09-04 | 88.4% | 70.3% | 1.2% | 42.7% | 499 |
| 2026-09-03 | 88.4% | 70.3% | 1.2% | 42.7% | 499 |
| 2026-09-02 | 88.4% | 70.3% | 1.2% | 42.9% | 499 |
| 2026-09-01 | 88.4% | 70.3% | 1.2% | 42.9% | 499 |
| 2026-08-31 | 88.4% | 70.3% | 1.2% | 42.9% | 499 |
| 2026-08-28 | 88.4% | 70.3% | 1.2% | 42.7% | 499 |
| 2026-08-26 | 88.4% | 70.3% | 1.2% | 42.7% | 499 |
| 2026-08-15 | 88.1% | 70% | 1.2% | 42.9% | 497 |
| 2026-08-10 | 88% | 70.3% | 1.2% | 43.2% | 498 |
Measured by Emailchaser over public DNS, 10 measurements since 2026-08-10, on a fixed panel of 499 business domains. This measures the domains a sender emails. It is not Emailchaser customer sending data.
Download all measurements (JSON)Related questions
Why do my emails land in spam for some people but not others?
Because recipient domains do not agree on what to do with mail that fails authentication. On 2026-09-05, 88.4% of measured domains enforce DMARC and 1.2% publish no DMARC record at all, so the same misconfigured send can be delivered by one and rejected by another. That pattern is a strong hint the problem is authentication, not content.
Will warming up a new domain fix spam placement?
Warmup helps reputation, which is the second factor, so it only helps once authentication is already correct. Warming a domain whose DKIM does not align just spends weeks building a reputation for mail that will keep failing.
How do I check whether my own domain is set up correctly?
Look up your own SPF, DKIM, DMARC and MX records and read what they actually say, rather than what you configured a year ago. Emailchaser's free deliverability test runs the same DNS checks used to build the panel measurement on this page.
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