--- title: Best Practices for Email Deliverability description: Learn what to avoid including in your emails so that you can avoid spam filters and maximize deliverability --- [Skip to content](https://kb.bigmarker.com/knowledge/best-practices-for-email-deliverability#main-content) English Show submenu for translations [![Size=36px, Style=On-light, Brand=BigMarker-1](https://kb.bigmarker.com/hs-fs/hubfs/Size=36px%2c%20Style=On-light%2c%20Brand=BigMarker-1.png?width=171&height=36&name=Size=36px%2c%20Style=On-light%2c%20Brand=BigMarker-1.png)](https://www.bigmarker.com/) Open main navigation Close main navigation - English Show submenu for translations Welcome to the BigMarker Knowledge Base! - There are no suggestions because the search field is empty. 1. [Knowledge Base](https://kb.bigmarker.com/knowledge?hsLang=en) 2. [Webinars and Series](https://kb.bigmarker.com/knowledge/webinars-and-series?hsLang=en) 3. [Emails & Invitations](https://kb.bigmarker.com/knowledge/webinars-and-series?hsLang=en#emails-invitations) # Best Practices for Email Deliverability ## Learn what to avoid including in your emails so that you can avoid spam filters and maximize deliverability Email clients will do their best to filter out spam messages and block unwanted messages for their users. To accomplish this, email messages are analyzed and scanned for a range of indicators that help determine whether they are legitimate. To help ensure your emails reach your intended audience, follow the guidelines below for all of your communications. ### Subject Line Red Flags - Words like "Free," "Guarantee," "Act now," "Limited time," "Winner," "Cash," "Click here." - Dollar signs and excessive numbers ($$$, 100% free). - Misleading subject lines that don't match the body content. - "Re:" or "Fwd:" prefixes when the email is not actually a reply or forward. ### Language & Wording Triggers - **Urgency language —** "Act now," "Don’t miss out," "Expires today." - **Money-related phrasing —** "Cash bonus," "Risk-free," "No cost." - **Exaggerated claims —** "Amazing," "Incredible," "Miracle." - **"This is not spam" —** Ironically, stating this often triggers filters. ### Content & Visual Elements - **GIFs and animated images —** Many spam filters flag animated content, and some email clients (older Outlook versions especially) render only the first frame or break entirely. - **Excessive emojis/emoticons —** Especially in subject lines; more than 1-2 in a subject line is a strong spam signal. - **ALL CAPS TEXT —** Especially in subject lines (e.g. "LIMITED TIME OFFER"). - **Excessive punctuation —** Multiple exclamation points/question marks (!!!, ???). - **Large embedded images with little text —** Image-only or image-heavy emails with minimal text trigger filters (looks like an attempt to hide spam text from scanners). - **Hidden or white text —** Any text matching the background color. - **Excessive font colors/sizes —** Rainbow text or multiple font changes within one email. ### Links & URLs - **URL shorteners —** (bit.ly, tinyurl, etc.) — these obscure the destination and are heavily flagged. - **Mismatched display text vs. actual URL —** Link text says one thing, hover reveals another. - Too many links relative to the amount of text in the email. - Links to domains with poor reputation or newly registered domains. - IP address links instead of domain names. ### Technical & Structural Issues - **Broken HTML —** Unclosed tags, sloppy or invalid markup. - Large attachments or unusual file types (.exe, .zip, .scr). - **No physical mailing address in the footer —** A CAN-SPAM Act requirement in the US. - **Poor text-to-HTML ratio —** Too much markup relative to actual content. ### Invite List Hygiene Issues - Sending to purchased or unverified lists. - No segmentation — blasting the same email to everyone regardless of engagement. - Sending to old or stale lists with high inactive-address rates, which hurts sender score.   - [Getting Started](https://kb.bigmarker.com/knowledge/getting-started?hsLang=en#main-content) - [BigMarker Basics](https://kb.bigmarker.com/knowledge/getting-started?hsLang=en#bigmarker-basics) - [Intro to presenting](https://kb.bigmarker.com/knowledge/getting-started?hsLang=en#intro-to-presenting) - [Basics of the attendee experience](https://kb.bigmarker.com/knowledge/getting-started?hsLang=en#basics-of-the-attendee-experience) - [BigMarker Troubleshooting](https://kb.bigmarker.com/knowledge/getting-started?hsLang=en#bigmarker-troubleshooting) - [Hardware and Device Troubleshooting](https://kb.bigmarker.com/knowledge/getting-started?hsLang=en#hardware-and-device-troubleshooting) - 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