Who This Is For / When to Use
Account owners sending email campaigns, broadcasts, or workflow emails.
Users experiencing low open rates or emails landing in spam.
Teams setting up email infrastructure for the first time in Kyrios.
Why Email Deliverability Matters
Email deliverability determines whether your emails reach the inbox or are filtered as spam.
Poor deliverability can result in:
Missed communications
Low engagement rates
Long-term damage to your sending reputation
Following the practices below helps protect your domain reputation and ensures consistent inbox placement.
Use a Dedicated Email Sending Domain
What this means
A dedicated sending domain is a domain used only by your account for sending emails.
Why this matters
Shared domains inherit the reputation of other senders. A dedicated domain gives you full control over deliverability.
Best practice
Use a domain you own (example:
mail.yourbusiness.com)Authenticate the domain before sending campaigns
Warm up new domains gradually
Use a Proper “From” Email Address
What this means
The “From” email address is what recipients see in their inbox.
Why this matters
Mailbox providers verify that the “From” address matches your authenticated domain.
Best practice
Use an address on your sending domain (example:
[email protected])Do not use mismatched or generic addresses
Always Include an Unsubscribe Link
What this means
An unsubscribe link allows recipients to opt out of future emails.
Why this matters
Required for compliance with email regulations
Prevents spam complaints
Protects your sender reputation
Best practice
Include an unsubscribe link in every email
Use Kyrios’ default unsubscribe merge field or a clearly visible custom link
Avoid Spam Trigger Words and Formatting
What this means
Spam filters analyze content for language patterns commonly used in spam.
Why this matters
Overuse of promotional, misleading, or aggressive language increases spam risk.
Best practice
Avoid excessive use of:
ALL CAPS
Emojis
Multiple exclamation points (!!!)
Avoid phrases that promise unrealistic outcomes
Use clear, honest, conversational language
Maintain a Healthy Email List
What this means
List health refers to sending only to contacts who actively engage with your emails.
Why this matters
Sending to inactive contacts lowers engagement
High bounce or ignore rates hurt reputation
Best practice
Regularly remove inactive or unengaged contacts
Use smart lists based on last open or click activity
Avoid purchasing or importing cold lists
Handle Internal Emails Carefully
What this means
Sending emails from and to the same domain can appear suspicious to mail servers.
Why this matters
Mailbox providers may treat internal emails as spoofing attempts.
Best practice
Use an external email address (such as Gmail) for testing
For operational emails, whitelist your SMTP provider’s IP address with your domain host
Set Up and Verify DMARC
What this means
DMARC is an authentication policy that confirms your emails are legitimate.
Why this matters
Without DMARC, mailbox providers may reject or spam-filter your emails.
Best practice
Ensure SPF and DKIM are configured
Add a valid DMARC policy through your DNS
Confirm DMARC passes with your email provider
Do Not Send From Public Email Domains
What this means
Public domains include Gmail, Yahoo, Outlook, and similar free providers.
Why this matters
Bulk or automated emails from public domains are commonly flagged as spam.
Best practice
Always send from a domain you own
Match the sending domain to your brand
Secure Your Subscription Forms
What this means
Form security prevents fake or bot sign-ups.
Why this matters
Spam sign-ups harm list quality and sender reputation.
Best practice
Use double opt-in for email subscriptions
Add reCAPTCHA or verification where possible
Require confirmation before adding contacts to campaigns
Pro Tips for Better Deliverability
Segment your audience to send relevant content
Test emails before large sends
Warm up new domains slowly
Monitor bounce rates, spam complaints, and engagement metrics
Send consistent, value-driven content
Best Practices for Words to Consider Before Using
Below are some words and phrases that spam filters often view as red flags. Context will also assist. If you utilize only one or two of the words or phrases below, have a low bounce rate, and take other actions to ensure your emails comply with non-spam policies, you’ll be all set.
Spam Words:
#1
100% more
100% free
100% satisfied
Additional income
Be your own boss
Best price
Big bucks
Billion
Cash bonus
Cents on the dollar
Consolidate debt
Double your cash
Double your income
Earn extra cash
Earn money
Eliminate bad credit
Extra cash
Extra income
Expect to earn
Fast cash
Financial freedom
Free access
Free consultation
Free gift
Free hosting
Free info
Free investment
Free membership
Free money
Free preview
Free quote
Free trial
Full refund
Get out of debt
Get paid
Giveaway
Guaranteed
Increase sales
Increase traffic
Incredible deal
Lower rates
Lowest price
Make money
Million dollars
Miracle
Money back
Once in a lifetime
One time
Pennies a day
Potential earnings
Prize
Promise
Pure profit
Risk-free
Satisfaction guaranteed
Save big money
Save up to
Special promotion
Words that may pressure or create urgency for your leads:
Act now
Apply now
Become a member
Call now
Click below
Click here
Get it now
Do it today
Don’t delete
Exclusive deal
Get started now
Important information regarding
Information you requested
Instant
Limited time
New customers only
Order now
Please read
See for yourself
Sign up free
Take action
This won’t last
Urgent
What are you waiting for?
While supplies last
Will not believe your eyes
Winner
Winning
You are a winner
You have been selected
Words that may seem shady or lead to unethical behavior:
Bulk email
Buy direct
Cancel at any time
Check or money order
Congratulations
Confidentiality
Cures
Dear friend
Direct email
Direct marketing
Hidden charges
Human growth hormone
Internet marketing
Lose weight
Mass email
Meet singles
Multi-level marketing
No catch
No cost
No credit check
No fees
No gimmick
No hidden costs
No hidden fees
No interest
No investment
No obligation
No purchase necessary
No questions asked
No strings attached
Not junk
Not spam
Obligation
Passwords
Requires initial investment
Social security number
This isn’t a scam
This isn’t junk
This isn’t spam
Undisclosed
Unsecured credit
Unsecured debt
Unsolicited
Valium
Viagra
Vicodin
We hate spam
Weight loss
Xanax
Words that are often seen as jargon or legalese:
Accept credit cards
Ad
All new
As seen on
Bargain
Beneficiary
Billing
Bonus
Cards accepted
Cash
Certified
Cheap
Claims
Clearance
Compare rates
Credit card offers
Deal
Debt
Discount
Fantastic
In accordance with laws
Income
Investment
Join millions
Lifetime
Loans
Luxury
Marketing solution
Message contains
Mortgage rates
Name brand
Offer
Online marketing
Opt in
Pre-approved
Quote
Rates
Refinance
Removal
Reserves the right
Score
Search engine
Sent in compliance
Subject to…
Terms and conditions
Trial
Unlimited
Warranty
Web traffic
Work from home
FAQ
What is a dedicated email sending domain, and why do I need one?
A dedicated sending domain is a domain used only by your account for email delivery. It allows you to control your sender reputation and significantly improves inbox placement.
How do I reduce the chance of my emails being marked as spam?
Use a dedicated domain, authenticate your email, include unsubscribe links, avoid spam-trigger language, and maintain a clean email list.
Why is an unsubscribe link required?
Unsubscribe links are required for compliance and prevent recipients from marking your emails as spam, which protects your sender reputation.
How do I prevent internal emails from going to spam?
Avoid testing emails sent from and to the same domain. Use an external email address for testing or whitelist your SMTP provider’s IP address.
What is DMARC and how does it affect deliverability?
DMARC is an email authentication policy that verifies your messages are authorized. Proper DMARC setup reduces spam filtering and domain spoofing.
Can emojis, ALL CAPS, or excessive punctuation hurt deliverability?
Yes. Overusing emojis, capital letters, or punctuation can make emails appear spammy and increase filtering risk.
What is double opt-in and should I use it?
Double opt-in requires contacts to confirm their email address before receiving messages. It is the gold standard for list quality and strongly recommended.
Are there tools to test if emails might be flagged as spam?
Yes. Email testing tools can analyze content, formatting, and authentication to identify deliverability risks before sending.