Guide
Why Are My Emails Going to Spam?
Emails going to spam almost always trace back to one of three things: receivers can't verify you, they don't trust your domain yet, or recipients are complaining. Below are the 12 specific causes, how to spot each one and the fix.
- SPF Pass
- DKIM Not signing
- DMARC No record
- Gmail spam rate 0.34%
- Sends per mailbox 140 / day
- Blocklists Not listed
4 causes found
Start DKIM signing · add DMARC · cut volume · clean the list
Causes
Emails going to spam? The 12 most common causes
Roughly in the order to check them. The first two are settings you can fix today; the rest are about how you send.
| # | Cause | How to spot it | Fix |
|---|---|---|---|
| 1 | SPF or DKIM missing or broken | spf=fail, dkim=none or dkim=fail in the headers | Check SPF and DKIM |
| 2 | No DMARC, or DMARC not aligned | dmarc=fail, or no record at _dmarc | Fix DMARC |
| 3 | New domain or mailbox, no warmup | Domain registered recently, sending at full volume | Warm up first |
| 4 | Sudden volume spikes | Placement drops right after a big send | Cap each mailbox near 30/day; add mailboxes |
| 5 | Spam complaints of 0.3% or more | Spam rate in Google Postmaster Tools | Tighter targeting; aim under 0.1% |
| 6 | Poor list quality and bounces | Hard bounces, unknown-user errors | Verify before sending; remove bounces |
| 7 | Link shorteners and shared tracking domains | bit.ly-style links, a tool's default tracking domain | Full links; custom tracking domain or none |
| 8 | Spammy content | Many links or images, mixed content types | Run the spam checker |
| 9 | Shared IP reputation | Problems began with a new sending service | Choose a provider that polices its IPs |
| 10 | Blocklist listing | Your domain or a linked domain is listed | Fix the cause, then request removal |
| 11 | No easy unsubscribe for bulk mail | Recipients use Report spam to opt out | One-click unsubscribe; honor it quickly |
| 12 | Sending from a free Gmail address | @gmail.com sender, tool or volume mail | Send from your own domain |
Several of these are now published rules. Gmail and Yahoo require SPF or DKIM from every sender. Bulk senders, which Gmail and Outlook.com define as more than 5,000 messages a day, need SPF, DKIM and a DMARC policy of at least p=none. Gmail and Yahoo also want your spam rate below 0.3%, and Google recommends staying under 0.1%.
Diagnose
Why do emails go to spam? Find your cause in 5 steps
Don't guess. Each step rules out one group of causes, and the first one takes a minute.
Step 1
Read the headers
Open the message in Gmail, choose Show original and check SPF, DKIM and DMARC.
Step 2
Check DNS
Run the domain health checker for missing or broken records.
Step 3
Check spam rate
Google Postmaster Tools shows your Gmail spam rate per domain.
Step 4
Check blocklists
Look up your domain and any domain you link to.
Step 5
Test placement
Send to seed accounts and see where each copy lands.
Example: what passing authentication looks like in Show original
Authentication-Results: mx.google.com;
dkim=pass [email protected] header.s=google;
spf=pass [email protected];
dmarc=pass (p=QUARANTINE) header.from=acme.ioIf any of the three says fail or is missing, stop there and fix it with the domain health checker; nothing else matters until receivers can verify you. If all three pass, the problem is reputation or content: work through steps 3 to 5, and use an inbox placement test to confirm the fix before your next big send.
Test before you blame the content
Reputation
Volume, warmup and spam complaints
Causes 3, 4, 5 and 12 are about how much you send and who you send it to. Mailbox providers watch both closely for new senders.
- spam rate Google recommends staying under
- 0.1%
- spam rate Gmail and Yahoo tell you never to reach
- 0.3%
- messages a day makes you a bulk sender at Gmail and Outlook.com
- 5,000+
- Yahoo's deadline for honoring unsubscribes
- 2 days
New domains start with no trust
Spamhaus puts it plainly: unknown reputations begin as poor by default, and a good reputation takes longer to build than a bad one. Google's guidelines say to start with low volume to engaged recipients and increase slowly, avoiding sudden spikes if you don't have a history of sending large volumes. That is what warmup is.
A safe ramp for one new mailbox: cold emails per day
Jetmail planning example, not a provider rule. Pre-warmed mailboxes can start at the last step; 30 a day is Jetmail's planning ceiling per mailbox.
| Week 1 | 5 |
|---|---|
| Week 2 | 10 |
| Week 3 | 20 |
| Week 4+ | 30 |
Sending limits are a ceiling, not a target
A provider's daily limit tells you when it will stop you, not what is safe for cold outreach. Free Gmail accounts can send about 500 emails a day and Google Workspace accounts 2,000, yet cold email sent anywhere near those numbers from one mailbox is exactly the spike pattern filters punish. Spread volume across mailboxes and domains instead.
Daily sending limits vs a cold email plan, per mailbox
Provider limits from Google's help pages, October 2026. 30/day is Jetmail's planning assumption for cold email.
| Google Workspace | 2,000 |
|---|---|
| Free Gmail | 500 |
| Workspace trial | 500 |
| Cold email plan | 30 |
Sending from free Gmail
A free @gmail.com address has a 500-a-day cap, no domain of your own to build reputation on and no way to set SPF, DKIM or DMARC. Sending it through another tool or server is worse: Google's guidelines say not to impersonate Gmail From: headers, and when we checked in October 2026, gmail.com published a DMARC policy of p=none; sp=quarantine while yahoo.com published p=reject. Outreach belongs on a domain you control.
Google Workspace
Google Workspace emails going to spam
Workspace sends from Google's own infrastructure, so when its mail lands in spam the cause is usually on your side of the setup.
- DKIM was never started. Until you generate a key under Apps › Google Workspace › Gmail › Authenticate email, publish it and click Start authentication, Gmail doesn't sign with your domain's key. Google says it can take up to 48 hours to start working. Confirm with the DKIM checker.
- SPF is missing Google. Your one SPF record must include
include:_spf.google.com. Two SPF records break both. See the Google Workspace SPF record. - No DMARC record. Publish one at
_dmarc, starting atp=nonewith a reporting address, using the DMARC generator. - Cold email from your main domain. Send outreach from separate domains, about 3 mailboxes each, so a reputation dip never reaches your invoices and support replies.
- Too much, too soon. Brand-new Workspace mailboxes sending hundreds of cold emails a day trip every volume signal. Ramp up as above, or start with pre-warmed inboxes.
Start with infrastructure that's set up right
Jetmail creates Google and Microsoft mailboxes on separate domains with SPF, DKIM and DMARC already published, or pre-warmed ones that can send from day one.
Links & reputation
Links, content and shared reputation
Causes 7 to 11 are the ones that survive a perfect DNS setup.
Link shorteners and tracking domains
Shorteners hide where a link goes, which is why spammers use them. Spamhaus keeps a separate shortener zone in its Domain Blocklist that filters can use to block or score mail. Click tracking has the same problem in a different form: in tools like Instantly, tracked links go through a tracking domain shared with every other customer unless you set up your own. Instantly's own help center recommends a custom tracking domain to keep your reputation separate. For cold email, plain full links, or no tracking at all, are simplest.
Content
Google's guidelines ask for links that are visible and easy to understand, and say not to mix different types of content in one message, such as a promotion inside a receipt. For cold outreach that means short plain text, one link at most and no attachments in the first email. Check a draft with the spam word checker.
Shared IPs and blocklists
On a shared IP, other senders' behavior affects you; Google tells senders on shared IPs to make sure the address isn't on any blocklist. Domain blocklists matter just as much. Spamhaus checks domains in your headers and in links inside the message, so linking to a listed domain can hurt mail that is otherwise clean.
Bulk senders: unsubscribe is a requirement
Prevention
How to prevent email from going to spam
- Publish one SPF record, turn on DKIM signing and add a DMARC record for every sending domain.
- Send cold email from separate domains, never your main company domain.
- Warm new mailboxes up over several weeks, or start with pre-warmed ones.
- Keep each mailbox to about 30 cold emails a day and add mailboxes to scale.
- Verify every list before sending and remove hard bounces immediately.
- Write short plain-text emails with at most one full link and no attachments.
- Use a custom tracking domain, or turn tracking off.
- Make opting out easy, and keep your Gmail spam rate under 0.1% in Postmaster Tools.
- Monitor blocklists and run an inbox placement test before big campaigns.
The full set of provider rules and thresholds is in the email deliverability guide. Jetmail's cold email infrastructure handles the first two steps for you, and pre-warmed inboxes cover the third.
Sources (checked October 2026): Google email sender guidelines · Gmail sending limits · Google Workspace sending limits · Google: set up DKIM · Yahoo sender best practices · Microsoft: Outlook requirements for high-volume senders · Spamhaus Domain Blocklist · Spamhaus: URL shortener zone · Instantly: custom tracking domain · DMARC policies from a DNS lookup of _dmarc.gmail.com and _dmarc.yahoo.com.
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Or see pricing →Frequently asked questions
Why are my emails going to spam all of a sudden?
A sudden change usually has a sudden cause: a DNS edit that broke SPF or DKIM, a jump in sending volume, a new list with more bounces or complaints, or your domain or a linked domain landing on a blocklist. Check your authentication headers and Google Postmaster Tools first.
Why is my email going to spam in Gmail but not Outlook?
Each provider scores mail with its own filters and its own view of your reputation, built from how its users react to your mail. Gmail tells senders to keep the spam rate shown in Postmaster Tools below 0.3%. Check Gmail's verdict in Show original and your Gmail spam rate in Google Postmaster Tools.
How do I stop my emails from going to spam?
Authenticate with SPF, DKIM and DMARC, send from your own domain, ramp volume up slowly, email only people who expect to hear from you, remove bounces, keep messages plain with few links, and make opting out easy. Then test placement before big sends.
Why do emails go to spam even when SPF, DKIM and DMARC pass?
Passing authentication proves who sent the message, not that recipients want it. Filters then look at reputation: complaints, bounces, volume, blocklists and the links inside the message. Most persistent spam-folder problems are reputation problems.
Can a new domain make my emails go to spam?
Yes. Spamhaus notes that unknown reputations begin as poor by default, and Google asks senders to start with low volume and increase slowly. Warm a new domain up gradually, or use pre-warmed mailboxes that already have sending history.
Do spam words send emails to spam?
Rarely on their own. Words are one weak signal among many. A message heavy with sales language, links and images from a new domain is far more likely to be filtered than one word. Run a draft through a spam word checker, but fix authentication and reputation first.
How long does it take to fix emails going to spam?
Authentication fixes work as soon as DNS updates and signing starts; Google says new DKIM keys can take up to 48 hours. Reputation recovers more slowly, because it only improves as providers see you send wanted mail over time.