How does subject line length affect email deliverability and click-to-open rates on Yahoo and AOL?

Email marketer from Stack Overflow mentions that while subject line length is not a direct cause of deliverability issues, excessively long subject lines may be flagged by spam filters. They suggest keeping subject lines concise and relevant to avoid triggering these filters.

Email marketer from Email on Acid recommends leveraging preheader text to supplement short subject lines. This allows for more detailed messaging without sacrificing readability in the subject line itself, especially important for platforms with stricter length limitations.

Email marketer from Email Geeks explains that subject line length has zero impact on deliverability (assuming the email is RFC conform) and click through rates. Truncation depends on the app/device/UI used and the user's settings and advises that Matthieu stops chasing subject lines as the reason for CTO numbers and instead looks at total clicks vs. emails delivered, ignoring opens.

Email marketer from Reddit states that Yahoo Mail tends to truncate subject lines more aggressively than Gmail. They recommend testing subject lines on different Yahoo Mail interfaces (desktop and mobile) to ensure readability.

Email marketer from Campaign Monitor explains that subject lines around 41 characters had the highest open rates based on their research. However, they emphasize that it's crucial to balance length with clarity and relevance to maximize engagement.

Email marketer from HubSpot suggests that subject lines should be descriptive and to the point, and aim for under 60 characters to avoid truncation on most devices. Shorter, more direct subject lines can improve click-through rates if the offer or information is compelling.

Email marketer from Mailchimp shares that short subject lines can be effective, especially on mobile devices where screen space is limited. They suggest A/B testing different subject line lengths to see what resonates best with your audience, also recommending keeping subject lines under 9 words or 60 characters.

Email marketer from Vertical Response recommends keeping email subject lines to around 40 characters because longer subject lines can get cut off. It's important to make sure the important parts of the subject line are at the beginning to ensure more opens and click-throughs.

Expert from Email Geeks explains that user experience could be impacted by truncated subject lines. Recommends being aware of potential display truncation points, putting the most important info first, and being precise in the subject. Also recommends using preheader text to add additional context.

Expert from Word to the Wise explains that very long subject lines can be problematic, not for deliverability, but because they get truncated. This affects the user experience and might lower open rates. Prioritizing key information at the beginning of the subject line is crucial.

Documentation from Yahoo Help explains that subject line length can vary depending on the device and email client, but it's generally advisable to keep subject lines under 50 characters for optimal display on mobile devices. This helps ensure that key information isn't cut off.

Documentation from Litmus shares research showing how email clients like Gmail, Yahoo and Outlook truncate subject lines. The research highlights that there is a variety of subject line display lengths depending on whether you are using a desktop or mobile client.

Documentation from AOL Help suggests that while there isn't a hard limit, subject lines exceeding 70 characters may be truncated, especially on mobile devices. They recommend prioritizing the most important keywords at the beginning of the subject line.