How to Stop Emails Going to Spam: 7 Ways That Work in 2026

ATAbisola TanzakoJanuary 30, 202513 min read

Illustration of how to stop emails going to spam: an authenticated envelope carrying SPF, DKIM and DMARC marks passes a filter into the inbox while an unsigned envelope is routed to the spam folder

You sent the campaign and the opens never came. The message is sitting in a spam folder, where nothing you write next can reach it.

Knowing how to stop emails going to spam starts with why filters are hostile by default. Spam made up 44.99% of global email traffic in 2025, according to Kaspersky’s spam and phishing report for 2025, a decrease of 2.28 percentage points on the previous year. Filters sort that traffic every day, so an unfamiliar sender starts with no trust banked and has to earn it.

Below are seven strategies that stop emails landing in the spam folder, plus the sender requirements Gmail, Yahoo and Microsoft publish, linked so you can read them yourself.

Why are my emails going to spam?

Almost always one of four things: you have not authenticated your sending domain, your list is not clean, too many recipients marked your mail as spam, or your message does not represent itself accurately. Work through them in that order.

Diagram of the four causes of emails going to spam in the order to work through them: authenticate the sending domain with SPF, DKIM and DMARC; clean the list by exporting a copy and removing only the hard bounces your last send reported; bring down spam complaints with a working unsubscribe link and segmentation; and make the message represent itself so the subject and display name match what was sent

Here is what filters weigh before they decide.

Sender reputation. Your sender reputation works like a credit score for your email. Providers track the sending domain and IP address behind your messages, and Google’s guidelines say that over time, user spam reports can lower your domain’s reputation.

Content. Filters read what you send, but Google’s email sender guidelines are not a banned-word list. Google’s display-name guidance tells senders to identify the sender first and not to include subject or message content in the display name, and says misuse of display names can impact deliverability to personal Gmail accounts. The rule is about not misleading anyone, not about a forbidden vocabulary.

Email structure. Subject lines that misrepresent the message raise suspicion. Google also tells senders not to use HTML and CSS to hide content in messages, because hiding content might cause messages to be marked as spam. The same guidelines set message-format rules for your headers, including a valid Message-ID, headers that appear only once, and a single address in the From: line, which is work for whoever configures your sending platform.

Recipient engagement. Spam complaints are the engagement signal you can actually measure, and Google publishes a threshold for it. More on that below.

What Gmail, Yahoo and Outlook actually require

These are the published sender requirements, with each provider’s own figures.

What does Gmail require of senders?

Since February 1, 2024, every sender to Gmail accounts has been required to authenticate with SPF or DKIM. Senders of more than 5,000 messages per day to Gmail accounts must additionally set up DMARC and support one-click unsubscribe on marketing and subscribed messages.

What does Yahoo require of senders?

Under Yahoo’s sender best practices, Yahoo requires all senders to keep their spam rate below 0.3%, and bulk senders to publish a valid DMARC policy, support one-click unsubscribe and honor unsubscribes within 2 days. Yahoo’s page sets no message-volume number, so there is no send count that turns you into a bulk sender.

What does Outlook require of high-volume senders?

Microsoft’s requirements for high-volume senders landed in 2025: Microsoft requires domains sending more than 5,000 emails per day to Outlook.com addresses to comply with SPF, DKIM and DMARC.

Gmail, Yahoo and Outlook sender requirements at a glance

Provider and who it covers	What they require	Spam-rate limit
Gmail, all senders	SPF or DKIM on your sending domain	Below 0.10%, and never 0.30% or higher
Gmail, more than 5,000 messages per day	Adds DMARC, one-click unsubscribe and a clearly visible unsubscribe link on marketing and subscribed messages	As above
Yahoo, all senders	—	Below 0.3%
Yahoo, bulk senders	A valid DMARC policy, one-click unsubscribe, unsubscribes honoured within 2 days	Below 0.3%
Outlook.com, more than 5,000 emails per day	SPF, DKIM and DMARC	—

A dash means the published requirement quoted above states no figure for that column.

If you are still sending campaigns from a general-purpose mailbox, this is the point where that stops working. Arkesel Email Marketing handles campaigns, automation flows, contact segmentation, A/B and split testing, and transactional email from one platform.

Is there a 60/40 text-to-image rule for email?

No. No provider requirement specifies a text-to-image ratio.

We read all three published documents on 13 August 2026: Google’s email sender guidelines, Yahoo’s sender best practices, and Microsoft’s requirements for high-volume senders. None of them names any ratio between text and images. It is a rule of thumb, not a published requirement, and it does not come from the companies that run the filters.

The point underneath it still holds without a number attached. An email built as one large image with no live text is the real risk, because a reader whose client blocks images sees nothing at all. Write the message as text, let images support it, and give every image descriptive alt text so it still reads when the images do not load.

You can test that in a minute. Open the finished campaign in your own email client with images switched off, and check that the message still reads and the action you want is still obvious.

7 ways to stop your emails going to spam

1. Build a strong sender reputation

Collect addresses with permission. Google’s sender guidelines tell senders not to purchase email addresses from other companies, and to send only to people who signed up. Sign-up forms and double opt-in are how you do that in practice, and our guide to building a permission-based list covers the mechanics.
Increase volume slowly on a new domain. Google’s guidance on ramping up sending volume is to start with a low volume to engaged users and increase it slowly over time, with no specific daily numbers given. There is no official warm-up schedule to copy, so let your bounce and complaint numbers set the pace.
Keep the list clean, in this order. Export a copy of your list first, because a sending platform will not hand back an address you have deleted. Then remove only the addresses your last send’s bounce report labelled a hard bounce — those are the invalid ones, and Yahoo tells senders to remove invalid recipients from their list promptly. Leave the quiet-but-valid addresses where they are: Yahoo’s advice for inactive subscribers is a periodic reconfirmation email rather than a purge, which puts the decision back on the recipient. Keeping your email list clean is a habit worth building into your campaign routine rather than a rescue job.
Watch your reputation where the providers publish it. Register your sending domain with Google Postmaster Tools. Google’s guidelines describe what it gives you on the mail you send to Gmail users: when recipients mark your messages as spam, why messages might not be delivered as expected, whether your messages are authenticated, and your domain or IP reputation. Yahoo runs a separate Complaint Feedback Loop you enrol in once your mail is signed with DKIM — when a Yahoo user clicks report spam, you get a copy of the complaint, and Yahoo tells senders to use it to track their complaint rate against that 0.3% figure.

Three-stage diagram of safe email list cleaning: export a copy first, remove only hard bounces from the last send's bounce report, then send a reconfirmation email to quiet but valid addresses

2. Write content that represents itself

Match the subject line to the message. Keep it concise, relevant and accurate. Instead of “DON’T MISS THIS AMAZING DEAL!!!”, write what the email actually contains.
Get the display name right. Google’s own examples of display names to avoid read like shouted subject lines, because a display name should identify the sender rather than carry the pitch. Use your company name or a recognisable person, such as “Justina from ScriptureSpeaks”.
Personalise with data you hold. Address recipients by name, reference what they bought, send what matches their interests.
Include a plain text version. Send a plain text alternative alongside your HTML. It serves recipients who prefer text and clients that block HTML by default.

3. Set up email authentication: SPF, DKIM and DMARC

This is the strategy the table above pays off, and it is three records published in your domain’s DNS.

SPF lists the servers allowed to send mail for your domain.
DKIM signs your messages so a receiving server can check they were not altered in transit.
DMARC ties SPF and DKIM to the domain in your From: address and tells receiving providers what you want done when a message fails.

Here is how the three get published.

Publish them at your domain provider. Google’s instruction is to set up email authentication for each of your sending domains at your domain provider, which is the account where the domain itself is managed. You publish an SPF record at your domain, turn DKIM on for the domain that sends your mail, and publish a DMARC record for that domain.

Take the values from whoever sends your mail. Your SPF record should include every sender that sends for your domain, and in Google’s words, messages from a sender you leave out are more likely to be marked as spam. Google tells senders who use an email service provider to verify that the provider authenticates their domain with SPF and DKIM, and for DKIM it says to create your keys with one of the available internet tools or to ask your domain provider for help. None of these values is something you write from a template.

Start DMARC in monitoring, then tighten it. Gmail’s requirement for senders above 5,000 messages a day states that your DMARC enforcement policy can be set to none, and Yahoo asks bulk senders for a valid DMARC policy of at least p=none that passes. Yahoo strongly recommends including a rua tag properly set up to receive reports so you can monitor during initial setup, and Google recommends DMARC reports for the same reason. Publish the monitoring version, read what comes back, and only then decide what you want done with mail that fails.

Table diagram of the three email authentication records — SPF, DKIM and DMARC — showing what each one does and where its value comes from, all published at your domain provider

Do it first. Everything else on this list is worth less until it is done.

4. Design emails that survive a blocked-images inbox

Read it on a phone before anyone else sees it. Open the draft on your own handset and check that the offer, the one action you want and the unsubscribe link are all reachable without pinching or hunting.
Give every image descriptive alt text. The message must still make sense with images switched off, which is the real version of the image advice you have been given.
Include one clear call to action. Make the action you want obvious and easy to complete.
Test before you send. Check the campaign across the clients and devices your list actually uses, and send yourself a copy at Gmail, Yahoo and Outlook.com addresses to see where it lands.

5. Earn engagement, and watch the number that counts

Make unsubscribing easy. A visible unsubscribe link that works reduces complaints. Above Gmail’s threshold and for Yahoo’s bulk senders it is a requirement, not a courtesy.
Segment before you send. Segmenting your list by behaviour, purchase history or signup date is how relevance goes up and complaints go down.
Track the one metric providers publish. Google tells senders to keep the spam rate reported in Postmaster Tools below 0.10% and never to reach 0.30% or higher. That figure is set by your recipients and reported straight back to you.
Reply to replies. If people write back, answer. It is the cheapest trust signal you have with your own audience.

6. Choose a sending platform on the right criteria

Evaluate any provider you are considering against questions you can verify:

Can you authenticate your own domain, with SPF, DKIM and DMARC published on the domain you send from rather than the provider’s?
Does it report bounces and spam complaints back to you, campaign by campaign?
Can you connect the sending domain to Google Postmaster Tools?
Do you get a shared or a dedicated sending IP, and what happens to you if another sender on a shared IP behaves badly?
What do its terms and anti-spam policies require of you?

Arkesel Email Marketing covers the sending side: campaigns and newsletters, automation flows for welcome, follow-up and reminder sequences, contact segmentation, A/B and split testing, and transactional email. Take the checklist above to every provider you weigh up, this one included.

7. Stay current

Sender requirements changed twice in two years, and the pages that carry them are the ones to re-read: Google’s email sender guidelines, Yahoo’s sender best practices, and Microsoft’s high-volume sender requirements. Set a reminder to check them each quarter, and pair that habit with our email marketing best practices for the parts that change more slowly.

Do open rates measure email deliverability?

No. Google does not track email open rates, and says low open rates are not necessarily an accurate indicator of deliverability or spam classification issues. A flat open rate tells you something about your subject line, not about where your mail landed.

Watch these instead:

Your spam rate in Google Postmaster Tools, against the thresholds above. This is the one number Google scores you on.
Bounce rates from your sending platform, split into hard and soft bounces.
A seed test before every big send. Send the campaign to your own accounts at Gmail, Yahoo and Outlook.com and look at which folder it opens in.

Clicks and replies are still worth tracking. Read them as signals about your content, not about your deliverability.

What this means if you are sending from Ghana or elsewhere in Africa

The requirements are global. A sender in Accra meets exactly the same Gmail bar as a sender in Atlanta, so there is no regional exemption waiting to be found and no local workaround worth looking for.

Three local questions come up anyway, and every answer is procedural.

Does a .com.gh domain change anything? No. The published requirements are written about your sending domain and the address in your From: line — Google’s rule is that the authenticating domain must be the same domain that appears in the message From: header. Whatever your domain ends in, the job is the same three records on the domain you send from.

Which of the three pages actually binds you? The ones belonging to the providers your list sits on. Sort your contacts by the part after the @ and you will know inside a minute: a list weighted to Gmail and Yahoo addresses means those two pages are the ones to read first, and Microsoft’s page is the one to check if Outlook.com addresses are in there and your volume is climbing.

What if you are on a shared sending IP? Google’s guidance is blunt about the trade. A shared IP is one used by more than one sender, the activity of any sender on it affects the reputation of everyone on it, and a negative reputation can hurt your delivery rate — so if an email service provider gives you that shared IP, use Postmaster Tools to check the IP’s reputation. Your authentication records are yours to fix either way. Who else sends from that IP is not, which is why strategy 6 asks whether you get a shared or a dedicated one.

If you are running campaigns locally, email marketing in Ghana is the same discipline as anywhere else, done with a sender identity your customers know on sight. The same problem shows up on the SMS side, where filters and carrier rules punish the same shortcuts.

Get your emails into the inbox

Authenticate first, clean the list second, fix the content third. That sequence is how to stop emails going to spam for good, because no amount of subject-line work rescues a domain that never proved who it was.

Work through the seven strategies above, keep an eye on your spam rate, and re-read the three provider pages when they change. If you are still deciding what to send once the inbox is reachable, start with the types of email your business should be sending.

Ready to send from a platform built for campaigns, automation and transactional email? Create your Arkesel account and get your next campaign into the inbox.

How to Stop Emails Going to Spam: 7 Ways That Work in 2026

How to Stop Emails Going to Spam: 7 Ways That Work in 2026

Why are my emails going to spam?