Summary
Image-heavy emails pose challenges to deliverability and accessibility, particularly for telecom companies facing stringent legal requirements. While text/image ratio isn't the sole determinant of deliverability, it significantly impacts spam filter triggers. Accessibility mandates, like those from the Telecommunications Act, ADA, Section 508, and WCAG 2.1, require alt text for images, sufficient color contrast (especially in dark mode), and semantic HTML. Ignoring accessibility can lead to costly lawsuits. Large, unoptimized images increase loading times, and 'image spam' tactics can be penalized. Best practices include image optimization, a balanced text-to-image ratio (ideally 60:40 or higher), regular testing with screen readers, and adherence to WCAG guidelines.
Key findings
- Deliverability & Image Ratio: Spam filters penalize high image-to-text ratios. Balanced content improves delivery.
- Legal Obligations: Telecoms face specific legal demands (Telecommunications Act, ADA, Section 508) re: accessibility.
- Accessibility Reqs: Alt text, color contrast (WCAG 2.1), and semantic HTML are essential for accessible emails.
- Performance Impact: Unoptimized images cause slow loading, increasing abandonment.
- Legal Risks: Non-compliance can result in large fines and costly lawsuits.
Key considerations
- Content Balance: Maintain a 60:40 (or higher) text-to-image ratio to avoid spam filters and ensure accessibility when images are blocked.
- Image Optimization: Compress images (JPEG/PNG) to reduce file size and improve loading speed; utilize a CDN.
- Accessibility Support: Provide descriptive alt text for ALL images; test with screen readers. Check colour contrast ratios and dark mode compatibility.
- Semantic HTML: Use semantic HTML to structure emails for accessibility.
- Compliance: Ensure emails conform to WCAG 2.1 (and potentially higher versions as they are adopted) Level AA guidelines. Regularly check compliance requirements.
- Risk Mitigation: Consult legal counsel about ADA compliance. Implement Modular design for ease of creating accessible emails.
What email marketers say
13 marketer opinions
Image-heavy emails can negatively impact deliverability and accessibility, especially for telecom companies due to legal obligations like the Telecommunications Act and ADA. A balanced text-to-image ratio is crucial to avoid spam filters and improve engagement. Accessibility considerations include providing alt text for images, ensuring sufficient color contrast (especially in dark mode), and using semantic HTML. Optimizing images for size and load time is essential to prevent slow loading times. Telecom companies must also be aware of potential fines for non-compliance with accessibility standards. Modularity in email structure helps to ensure compliance.
Key opinions
- Deliverability: Image-heavy emails can trigger spam filters and reduce deliverability if a balanced text-to-image ratio is not maintained.
- Accessibility: Telecom companies have legal obligations to ensure email accessibility, including providing alt text for images and sufficient color contrast.
- Loading Times: Large, unoptimized images can significantly increase email loading times, leading to recipient abandonment.
- Dark Mode: Dark mode can invert colors, affecting readability and accessibility. Testing color schemes in dark mode is recommended.
- Legal Implications: Non-compliance with accessibility standards can result in fines and lawsuits, particularly for telecom companies.
Key considerations
- Text-to-Image Ratio: Maintain a balanced text-to-image ratio (60:40 or higher) to avoid spam filters and ensure information is accessible even if images are blocked.
- Image Optimization: Optimize images for size and format (JPEG or PNG) to reduce file size and improve loading times. Use a CDN for faster delivery.
- Alt Text: Provide descriptive alt text for all images to ensure accessibility for users with visual impairments.
- Color Contrast: Ensure sufficient color contrast, especially in dark mode, to meet WCAG guidelines and improve readability for low-vision users.
- Testing: Test email rendering across different email clients and test for accessibility issues, including color contrast and screen reader compatibility.
- Legal Compliance: Research and adhere to accessibility standards, such as the Telecommunications Act and ADA, to avoid legal consequences.
- Modular Email Structures: Implement modular email structures to easily reuse accessible elements and ensure compliance across different campaigns.
Marketer view
Email marketer from Sendinblue shares that images should be optimized for size and format before being used in an email. They recommend using formats like JPEG or PNG and compressing images to reduce file size. The source also mentions using a CDN to deliver images faster.
17 May 2025 - Sendinblue
Marketer view
Marketer from Email Geeks suggests researching potential fines for non-compliance with accessibility standards and uses HR Block and Southwest Airlines as examples of companies facing consequences.
8 May 2024 - Email Geeks
What the experts say
2 expert opinions
Image-heavy emails, especially those consisting solely of images (image spam), can negatively impact deliverability as modern spam filters analyze image content and penalize the lack of text. Additionally, failure to adhere to accessibility standards like WCAG 2.0 (and now 2.1) Level AA guidelines can lead to costly accessibility lawsuits.
Key opinions
- Image Spam: Using only images in emails is a tactic used by spammers and can negatively impact deliverability due to modern spam filter analysis.
- Accessibility Lawsuits: Failure to conform to WCAG 2.0 (and now 2.1) Level AA guidelines can result in expensive accessibility lawsuits.
Key considerations
- Text Content: Ensure emails contain sufficient text content to avoid being flagged as image spam and to provide context for spam filters.
- WCAG Compliance: Adhere to WCAG 2.0 (and now 2.1) Level AA guidelines to ensure accessibility and minimize the risk of accessibility lawsuits.
Expert view
Expert from Word to the Wise, in referencing an article by Seyfarth Shaw, reports that there have been a rising number of accessibility lawsuits relating to website accessibility. The advice here is that emails and websites need to conform to WCAG 2.0 (and now 2.1) Level AA guidelines, because accessibility lawsuits are expensive even if you win.
16 May 2022 - Word to the Wise
Expert view
Expert from Spam Resource explains that using only images in an email, often referred to as 'image spam', is a common tactic used by spammers to bypass text-based spam filters. However, modern spam filters can analyze image content and the lack of proper text can negatively impact deliverability.
16 Sep 2023 - Spam Resource
What the documentation says
5 technical articles
Ensuring accessibility in emails, especially for telecom companies, involves several key aspects as highlighted by W3C, Section508.gov, Litmus, ADA.gov, and WCAG. Providing descriptive alt text for images is crucial for users with visual impairments, enabling screen readers to convey the image's content. Section 508 mandates accessibility for federal agencies and organizations receiving federal funding. Accessibility in HTML emails requires semantic HTML, sufficient color contrast, and testing with screen readers. While the ADA doesn't explicitly address website or email accessibility, court interpretations extend its reach to digital platforms, making it relevant for telecom companies. WCAG 2.1 level AA requires a contrast ratio of at least 4.5:1 for text and images of text, improving readability for those with low vision or color deficiencies.
Key findings
- Alt Text Importance: Descriptive alt text is essential for image accessibility, allowing screen readers to convey image content to visually impaired users.
- Section 508 Mandate: Section 508 requires federal agencies and funded organizations to make electronic and information technology, including emails, accessible.
- HTML Accessibility Elements: Accessible HTML emails require semantic HTML, alt text, color contrast, and screen reader testing.
- ADA Implications: While not explicit, court interpretations of the ADA extend accessibility requirements to websites and potentially emails for companies providing public accommodation.
- WCAG Contrast Requirements: WCAG 2.1 Level AA mandates a 4.5:1 contrast ratio for text and images of text to ensure readability for users with low vision.
Key considerations
- Implement Alt Text: Always include descriptive alternative text for all images in emails to provide context for users with visual impairments.
- Adhere to Section 508: For organizations subject to Section 508, ensure emails comply with accessibility requirements.
- Use Semantic HTML: Utilize semantic HTML to structure emails for better accessibility and screen reader compatibility.
- Ensure Color Contrast: Verify sufficient color contrast (at least 4.5:1) to meet WCAG guidelines and enhance readability.
- Test with Screen Readers: Regularly test emails with screen readers to identify and address accessibility issues.
- ADA Compliance: Consider ADA implications and best practices for digital accessibility, particularly if your organization provides services to the public.
Technical article
Documentation from Web Content Accessibility Guidelines explains that WCAG 2.1 level AA requires a contrast ratio of at least 4.5:1 for text and images of text. Meeting these requirements ensures readability for people with low vision or color deficiencies.
6 Apr 2025 - Web Content Accessibility Guidelines (WCAG)
Technical article
Documentation from ADA.gov explains that while the ADA doesn't explicitly address website accessibility, courts have interpreted it to include websites as places of public accommodation. Telecom companies, providing services to the public, are often subject to these accessibility requirements.
11 Apr 2023 - ADA.gov
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