Why emails land in spam and how to prevent it
Email providers like Gmail, Outlook, and Yahoo use automated filters that watch for signs of spam — and legitimate emails get caught in those filters all the time. The filters look at where the email came from, how it was sent, what links and attachments it contains, and whether the sender's domain has a good reputation. If enough signals point to spam, the email goes to the spam folder instead of your inbox, and you never see it.
You can reduce the chance your emails get filtered by following the technical steps email providers care about most. These steps work whether you are sending emails from a personal account, a small business, or a domain you own. The most important ones take less than five minutes to set up.
Key Takeaways
- Add the sender's address to your contacts or mark their emails as "not spam" so your email provider learns to trust them.
- Ask senders to check that their domain has SPF, DKIM, and DMARC records set up, because missing records are the most common reason legitimate emails get filtered.
- Create email filters or rules in your email account to automatically move certain senders' emails to your inbox instead of spam.
- If you send emails that are getting filtered, check your email provider's sender reputation tool to see if your domain or IP address has a poor score.
Add the sender to your contacts or mark emails as not spam
The fastest way to protect an email from spam filtering is to tell your email provider you trust the sender. In Gmail, open the email and click the three dots in the top right, then select "Add to Contacts". In Outlook, right-click the sender's name and choose "Add to Safe Senders". In Yahoo Mail, click the three dots and select "Add to Contacts".
If you have already received emails from someone in your spam folder, open the spam folder, find their email, and click "Not Spam" or "Report Not Spam". Your email provider will move that email to your inbox and remember the sender for future messages. Do this for each sender you want to hear from — one contact at a time.
This method works when ready and does not require the sender to change anything on their end. It is the easiest step if you are receiving emails from someone you know and trust.
Create inbox rules or filters for specific senders
Email rules let you automatically sort incoming mail before it reaches spam. In Gmail, open Settings, go to Filters and Blocked Addresses, and click "Create a new filter". Type the sender's email address in the "From" field, click "Create filter", then check "Never send it to Spam". In Outlook, go to Settings, then Mail, then Rules, and create a rule that moves emails from that sender to your inbox. In Yahoo Mail, go to Settings, then Filters, and create a filter for the sender's address.
Rules are useful when you receive emails from a company or service regularly but their domain keeps getting flagged. Unlike adding a contact, a rule works even if the sender's address changes slightly or if they send from multiple addresses within the same company domain.
Check the sender's domain setup if emails keep getting filtered
If you are the one sending emails and they are landing in spam, the problem is usually that your domain lacks the authentication records email providers check. These records are called SPF, DKIM, and DMARC. They tell receiving email servers that your domain is real and that you authorized the emails being sent from it.
To add these records, you log into your domain registrar (the company where you bought your domain name — often GoDaddy, Namecheap, or your web host). You go to the DNS settings and add the records your email provider or email service gives you. Gmail, Outlook, and most email services provide the exact text you need to paste in. If you use a service like Mailchimp or ConvertKit to send emails, they usually provide the SPF and DKIM records you need to add to your domain.
Setting up these records takes 10 to 30 minutes the first time, but you only do it once. After the records are in place, email providers recognize your domain as legitimate, and your emails are much less likely to be filtered.
Monitor your sender reputation if you send bulk emails
If you send newsletters, notifications, or other bulk emails, your domain and IP address build a sender reputation — a score that email providers use to decide whether to filter your mail. Gmail, Outlook, and Yahoo all offer tools to check your reputation. In Gmail, go to Postmaster Tools and sign in with your domain. In Outlook, use the SNDS (Sender Score) tool. These tools show you if your domain is on any spam blacklists and whether recipients are marking your emails as spam.
If your reputation is poor, the most common causes are that people are marking your emails as spam, you are sending to addresses that do not exist, or your domain lacks SPF and DKIM records. Fix the records first, then make sure you are only sending to people who signed up to receive your emails. Remove addresses that bounce back as undeliverable, because sending to invalid addresses damages your reputation further.
Use a dedicated email service for newsletters and marketing
If you send regular newsletters or marketing emails, sending them directly from your personal or business email account can hurt your domain's reputation if even a small percentage of recipients mark them as spam. Email services like Mailchimp, ConvertKit, Substack, and Brevo are built to send bulk mail in a way that protects your domain. They manage sender reputation, handle bounces, and provide the SPF and DKIM records you need.
These services also let you see how many people opened your emails and clicked links, which helps you understand whether your emails are reaching inboxes or spam folders. If you send more than a few hundred emails a month, using a dedicated service is usually worth the time it saves and the protection it gives your domain.
Avoid common mistakes that trigger spam filters
Certain email practices almost always get flagged. Do not use all capital letters in the subject line, do not include too many links or attachments, and do not use urgent language like "Act now" or "Limited time". Spam filters are trained to recognize these patterns. If your email contains a link to a file read or a suspicious-looking URL, it is more likely to be filtered — especially if the link is shortened or obscured.
If you are sending from a new domain or IP address, email providers are cautious by default. Start by sending to a small group of people you know, wait a few days, then gradually increase the volume. This builds your sender reputation slowly and safely. Sending thousands of emails on day one from a brand-new domain will almost certainly trigger filters, even if the emails are legitimate.
Frequently Asked Questions
Why do emails from my bank or credit card company keep going to spam?
Banks and financial companies often send emails from multiple servers and domains, which can confuse spam filters. Add the bank's official email address to your contacts and create an inbox rule for their domain. If it keeps happening, contact the bank's customer service and ask them to check their SPF and DKIM records — they may have misconfigured them.
Does marking an email as "not spam" teach my email provider to trust that sender forever?
Marking an email as not spam helps, but it is not permanent. Your email provider learns from that action, but if the sender's domain has a poor reputation or lacks proper authentication records, future emails may still be filtered. Adding the sender to your contacts is more reliable than marking individual emails as not spam.
If I create an inbox rule for a sender, will old emails in spam move to my inbox automatically?
No. Inbox rules only affect new emails going forward. You have to manually move old emails out of spam or delete them. Open your spam folder, find the emails from that sender, select them, and click "Move to Inbox" or "Not Spam".
Can I get my domain removed from spam blacklists?
Yes, but you have to fix the underlying problem first. Check which blacklist your domain is on using a tool like MXToolbox, then follow that blacklist's removal process. Most require you to fix your SPF and DKIM records, stop sending to invalid addresses, or reduce the number of spam complaints. After you fix the problem, submit a removal request and wait — removal usually takes a few days to a week.
What should I do if a company tells me their emails are getting filtered and asks me to add them to my contacts?
Add them to your contacts if you trust them, but also ask them to check their domain setup. A legitimate company should have SPF, DKIM, and DMARC records in place so their emails reach inboxes without requiring customers to take extra steps. If they cannot explain what those records are, that is a sign their email infrastructure may not be set up properly.