Summary
Sending emails with content in multiple languages can significantly boost engagement with diverse audiences. However, it introduces specific technical and strategic considerations to maintain strong email deliverability. While the presence of multiple languages itself typically does not directly trigger spam filters, incorrect implementation of character sets or HTML language attributes can lead to display issues or accessibility problems, indirectly affecting user engagement and, consequently, sender reputation.
Key findings
- Direct deliverability impact: The mere inclusion of multiple languages within an email, when correctly formatted, generally does not negatively impact deliverability or trigger spam filters directly, nor does it typically lead to being placed on an email blocklist.
- Technical correctness: Proper HTML structure, particularly the use of lang attributes and correct character encoding (like UTF-8), is crucial for ensuring emails display correctly across various email clients and devices. This is an important part of email code quality.
- Accessibility: Using appropriate language tags helps screen readers and other assistive technologies correctly interpret the content, improving accessibility for recipients.
- Engagement: Sending emails in a recipient's preferred language significantly enhances comprehension and engagement, leading to better open and click-through rates. This can indirectly improve your sender reputation over time, as positive engagement signals good sending practices.
- Localization vs. translation: Beyond mere translation, true email localization involves adapting content, imagery, and cultural nuances to resonate with specific regional audiences. Simply translating can sometimes lead to misunderstandings or offense, as noted by Mailjet.
Key considerations
- Character set: Always use UTF-8 as your email's character set. It supports a wide range of characters from different languages, preventing display issues like garbled text. For more on this, read our guide on UTF-8 and deliverability.
- HTML language attributes: Set the primary language of the email in the <html> tag (e.g., <html lang="en">). For sections of text in a different language, apply the lang attribute to the specific HTML element containing that text (e.g., <p lang="es">). This nested approach is best practice for accessibility and parsing.
- Segment your audience: If possible, segment your email list by language preference. This allows you to send fully localized emails, which often perform better than mixed-language messages.
- Testing: Always test your multi-language emails across various email clients and devices to ensure correct rendering and display of all characters and content.
What email marketers say
Email marketers often approach multi-language sending from a practical perspective, focusing on user experience and engagement. Their primary concern is ensuring messages are understood by the target audience without compromising inbox placement. While they might not delve into the deepest technicalities, they emphasize the importance of clear communication and correct rendering to avoid recipient frustration and negative feedback that could harm their sender reputation.
Key opinions
- Audience focus: Marketers prioritize reaching their intended audience effectively, even if it means including a small section in a different language for a specific community, such as Hispanic communities in the US.
- User experience matters: The goal is to make content accessible and comprehensible. If recipients can't read the content, engagement drops, which is a key factor in email deliverability.
- Simplicity is key: For simple mixed-language emails (e.g., English primary with a Spanish paragraph), marketers generally don't expect major deliverability issues, assuming basic technical hygiene.
- Engagement as a metric: Successful multilingual campaigns are those that see improved open rates, click-through rates, and conversions because the message resonates with the recipient in their preferred language. This directly affects email click-through rates.
- Beyond translation: While direct translation is a start, marketers acknowledge that true multilingual email marketing requires adapting to cultural contexts.
Key considerations
- Target audience: Clearly define which audiences will receive which language combinations, especially when targeting specific communities like US Hispanic groups.
- Content placement: Consider placing secondary language content strategically, for instance, at the bottom of an email, to avoid disrupting the flow for the primary language audience.
- Test different versions: A/B test different approaches to multi-language content, including segmentation versus mixed content, to see what resonates best with your audience and optimize for engagement.
- List segmentation: Ideally, segment your list by language preference to send highly relevant, single-language emails. If this isn't possible, mixed-language emails can serve as a compromise.
- Feedback loops: Monitor feedback loops and spam complaints closely. A sudden increase after implementing multi-language emails could indicate issues with content relevance or rendering for certain recipient groups.
Marketer view
Marketer from Email Geeks indicates they aim to send more Spanish language content, primarily targeting Hispanic communities in the US. They are curious about potential deliverability issues and the correct use of HTML lang tags when mixing English and Spanish in the same email, particularly if the Spanish portion is just a small paragraph at the bottom.
Marketer view
Email Marketer from SendLayer highlights the importance of testing when sending emails in multiple languages. They advise creating different versions of your emails to identify which ones achieve better engagement rates.
What the experts say
Email deliverability experts focus on the technical implementation and its indirect effects on sender reputation. Their consensus leans towards minimal direct deliverability impact from mixed languages if proper HTML and character encoding standards are followed. The main concerns revolve around ensuring content renders correctly and provides a good user experience, as these factors ultimately influence recipient engagement and spam filtering decisions.
Key opinions
- Minimal direct impact: Experts generally agree that mixed-language content itself is unlikely to cause delivery issues or trigger spam filters, provided the email is technically sound.
- HTML lang attribute: Correctly applying the lang attribute to specific HTML elements for different language sections is recommended for accessibility and proper rendering, rather than trying to apply multiple languages to the entire <body> tag.
- Character encoding: Ensuring the email uses the UTF-8 character set is paramount to prevent display problems with non-English characters. This aligns with broader email encoding best practices (see our article on UTF-8 vs. Base64).
- Technical cleanliness: Overall technical hygiene, including valid HTML and correct encoding, is more important than the language mix itself. Issues here could affect how emails fail deliverability checks.
- International sending best practices: For broader international audiences, additional best practices like double opt-in are often recommended to maintain good deliverability, as noted by Salesforce.
Key considerations
- Granular language tagging: Apply lang attributes to specific HTML blocks or paragraphs rather than the entire document if languages are mixed. Set the primary language on the <html> tag.
- UTF-8 encoding: Always declare and ensure your email content is encoded in UTF-8. This is critical for displaying special characters correctly across all languages.
- Impact on engagement: Recognize that poor rendering due to incorrect encoding or language tags can lead to a negative user experience, resulting in lower engagement metrics and potentially higher spam complaints, which can hurt your domain reputation.
- Region-specific language codes: While less critical for deliverability, using more specific language codes (e.g., es-419 for Latin American Spanish) can enhance accessibility and localization for screen readers and specific regional software.
Expert view
Expert from Email Geeks suggests that for accessibility and HTML correctness, language attributes should be applied to the specific HTML containers holding the text of each language. For example, use lang="en" for English sections and lang="es" for Spanish sections, rather than attempting to apply both to the main <body> tag.
Expert view
Expert from Spam Resource highlights that email deliverability isn't solely about avoiding spam filters but also ensuring emails are well-formatted and accessible to all recipients. Incorrect language encoding can lead to display issues that frustrate users, indirectly affecting sender reputation.
What the documentation says
Official web and email standards, such as those from the W3C and various RFCs, provide guidelines for handling multilingual content. These documents primarily emphasize the importance of declaring character sets and using language attributes for proper rendering, accessibility, and machine readability. While they don't directly address email deliverability in the context of spam filtering, adhering to these standards ensures the technical integrity of your email, which is foundational for reliable delivery and a good recipient experience.
Key findings
- HTML lang attribute: The HTML specification (e.g., HTML 4.01, HTML5) recommends using the lang attribute on HTML elements to specify the natural language of the content. This allows user agents (like email clients or screen readers) to render the text appropriately. For mixed languages, it should be applied to the specific element containing the different language, not just the root.
- Character encoding: Internet standards (like RFC 2045 for MIME) dictate that email content must specify its character set. UTF-8 is the universally recommended encoding for its ability to represent characters from all languages, preventing display issues.
- Accessibility guidelines: Web Content Accessibility Guidelines (WCAG), which are highly relevant to email design, require that the human language of each passage or phrase in the content can be programmatically determined. Using lang attributes fulfills this requirement, benefiting users with assistive technologies.
- Language sub-tags: RFC 5646 (BCP 47) defines language tags like es-419 (Spanish for Latin America) that allow for more precise language identification, though basic tags like es are often sufficient for general rendering purposes.
Technical article
The W3C HTML 4.01 Specification for Language Information highlights that the lang attribute can be used in HTML to specify the base language of the element's content. This allows user agents to render content more accurately and select appropriate language-specific resources.
Technical article
Mailjet's best practices guide on email localization states that effective global email strategy goes beyond simple translation. It requires deep cultural understanding to ensure messages resonate correctly with diverse audiences and avoid misinterpretations that could damage brand perception.
Related resources
15 resources
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