How to Prevent Emails from Ending up in the Spam Folder

There are steps you can take to prevent your emails from ending up in your recipient’s Spam folders. We’ve listed some of the best practices you should follow –

IP Address Warming

Spammers often create new IP addresses and send large volumes of unwanted emails. To safeguard against this, Inbox service providers (ISP) treat mail received from new or ‘cold’ IP addresses with suspicion and are also sensitive to initial email volume.

When you start to use LeadSquared’s email campaigns feature, the IP addresses assigned to you have never been used to send emails before. To build up a positive sender reputation, ensure better email deliverability, and prevent your emails from ending up as spam, it’s essential to warm up your IP.

To warm up your IP, start by slowly and methodically sending small volumes of email, and then gradually ramping up to moderate and higher volumes. The objective is to build up approximately 30 days of sending history and data to familiarize ISPs with emails coming from your new IP address. It’s also important to be mindful of your list quality, email content, and subscriber engagement.

Here’s what you should do –

  • Start by sending small volumes of emails, and increase the volume gradually.
    See the *Sample IP Warming Schedule below.
  • Ensure the content you send early on is highly engaging.
    You want to start by sending your most engaging emails to interested target audiences. Maximize the likelihood that users click, open, and interact with your email.
  • Keep your email lists clean. Remove old and unverified email addresses.
    Maintain the quality of your email lists to minimize bounce rates and spam metrics, and maximize your sender reputation.
  • Continue to send emails at a consistent cadence.
    IPs may cool down if volume stops or decreases significantly for more than a few days.

*Sample IP Warming Schedule

Keep your bounce rate low (below 10%) and your spam complaint rate below 0.1% and continue to increase your sending per day over the next few weeks. Continue ramping up till you reach your required sending volume.

DayNumber Of Emails To Be Sent
18+Double Daily Until Desired Volume


More Best Practices

  1. Include a text version of your email
    Including a text version of your email in HTML emails is the easiest way to avoid emails ending up in the spam folder. You are greatly reducing the chances of your email being filtered as SPAM.
    Also, Microsoft Outlook includes an auto-preview feature that displays the first 3 lines of your email. This gives your recipients a chance to preview your email before deciding to open it. By default, the auto-preview will display the first few lines of your text email.
    Always try and provide a relevant summary of the contents of your email in the first few sentences in the text version of the email.
  2. Maintain a good text to image ratio
    Usually spam filters cannot identify images, and so if you include more images, it is likely to end up in the Spam folder.
  3. Avoid spam trigger words and phishing phrases
    Some phrases like “Once in a lifetime opportunity, “Click here, “Make billions and so on would easily catch the attention of spam filters. Also avoid too many exclamation marks and using all caps.
  4. Keep the subject of the email relevant
    The subject line is the easiest way to get your email filtered as spam. Keep it short and simple.
  5. Avoid large attachments and certain attachment types
    Avoid executable attachments such as, etc. As a general rule, you shouldn’t send attachments to people on your list that aren’t expecting them. You can instead include a link in the email to download the file/attachment.
  6. Code your HTML email properly
    If your HTML Email code is bad, you appear as a spammer. Broken images, missing tags, and non web-safe colors are some of the things spam filters look for.
  7. Make sure your emails are authenticated
    Some spam filters will check to make sure that an email claiming to be originating from a domain name actually did originate from that domain name. This is called authentication and it is slowly becoming more and more common. Emails that are not “authenticated” are either classified as “junk” or flagged as “suspicious.”
  8. Ensure your DKIM and SPF are setup properly
    The DKIM record allows LeadSquared to digitally sign your emails for your domain. Without this record, LeadSquared’s email provider still adds this to your emails, but it’s signed for the sending party’s sending server instead of your domain. For more information on this, see Email Link Domain and DKIM/SPF Settings for LeadSquared.
    When you add the SPF record to your domain, that allows receiving email servers like Hotmail, Gmail, Yahoo, and others, to verify the identity of your emails for the SenderID authentication. If somebody else such as LeadSquared is sending Emails on your behalf, then that SPF record explicitly gives permission to LeadSquared to send email on your behalf.
  9. Be compliant with the CAN-SPAM Act
    The CAN-SPAM Act, a law that sets the rules for commercial email, establishes requirements for commercial messages, gives recipients the right to have you stop emailing them, and spells out tough penalties for violations. Here are a few points to help you stay compliant –

    • Don’t use false or misleading header information.
    • Don’t use deceptive subject lines.
    • Identify the message as an ad.
    • Tell recipients where you’re located.
    • Tell recipients how to opt-out of receiving future emails from you.
    • Honor opt-out requests promptly.
    • Monitor what others are doing on your behalf.

For more detailed requirements, see CAN-SPAM Act.


Any Questions?

If you’ve encountered issues and discovered some new tips and tricks, we’d love for you to share them in the comments section below.

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1 year ago

Hi Karthik,

We are done with CNAME and Domain settings our Marketing campaigns emails are going to promotions(not every time) even though if we are giving simple texts in this case CRM doesn’t work, so shall you give any tips and tricks or as I have gone through few articles and webinar’s we can go with integration to WARMUP inbox initially.


Sri Sudhan
Reply to  Prashanthi
1 year ago

Hi, Prashanthi. To make your marketing emails reach your inbox, you need to have a dedicated IP setup for your domain. To obtain this setup, write to for more details. Hope this helps.