Linking directly to PDFs from emails doesn't automatically doom deliverability, but it introduces several potential pitfalls. While some experts believe direct links are acceptable, especially when the PDF is hosted on a reputable server, the consensus leans toward caution. Key concerns include the risk of PDFs containing malware, triggering spam filters, or being blocked by mail clients. A common recommendation is to link to a webpage containing the PDF instead, which allows for better tracking, branding opportunities, and a more user-friendly experience. Furthermore, maintaining a strong sender reputation by adhering to email authentication best practices (DKIM, SPF), regularly checking link reputation, and avoiding links to suspicious sites are crucial for ensuring positive deliverability outcomes, regardless of whether you're linking to PDFs or other types of content.
9 marketer opinions
Linking directly to PDFs from emails doesn't definitively harm deliverability, but it presents potential risks. Experts recommend caution, emphasizing the importance of a reputable PDF source and secure hosting. Some suggest avoiding direct PDF links altogether in favor of linking to a webpage containing the PDF, allowing for better tracking, branding, and user experience. A key concern is that PDFs can be flagged as spam or harbor malicious content, negatively affecting sender reputation. General email deliverability best practices, such as maintaining a clean domain, using link checkers, and avoiding suspicious URLs, also apply.
Marketer view
Email marketer from Mailjet Blog explains that linking directly to PDFs doesn't directly harm deliverability if the PDF is legitimate and hosted on a reputable server. However, they caution that if the PDF is flagged as spam or contains malicious content, it can negatively impact your sender reputation.
21 Jul 2023 - Mailjet Blog
Marketer view
Email marketer from HubSpot shares tips on email deliverability and how to ensure your emails are not flagged as spam. They do not mention PDFs but say to ensure your links lead to trusted sites.
27 Jan 2025 - HubSpot
4 expert opinions
While direct PDF links aren't inherently detrimental, experts highlight potential risks to email deliverability. Concerns include malware within PDFs, enterprise mail filters scrutinizing links, and the impact of URL reputation. Testing direct PDF links is advised, with a fallback option of using a 'download' link if issues arise. Linking to webpages with PDFs is favored for enhanced tracking, branding, and user support. Google's potential penalties based on landing page content should also be considered.
Expert view
Expert from Email Geeks explains links to PDFs should be tracked by ESPs, but there is less visibility on the website performance of the link. Ideally, the PDF should be on a page for branding/upselling opportunities. It could be harder for the recipient to resolve any issues if the PDF link breaks directly from an email, compared to a website.
4 Dec 2024 - Email Geeks
Expert view
Expert from Email Geeks doubts linking directly to PDFs will cause issues and says it's better than attaching PDFs to emails, although PDFs can contain malware and enterprise mail filters might check the links.
28 Mar 2023 - Email Geeks
3 technical articles
While direct PDF links aren't specifically addressed, email deliverability documentation from Google, RFC and Microsoft offers relevant guidance. Authenticating your sending domain with DKIM and SPF builds trust, improving deliverability for all links, including PDFs. Email clients may block unsafe file types, which often includes PDFs, highlighting the importance of ensuring your PDF content is secure. Overall email sending best practices such as properly formatted emails and freedom from malicious content are key to avoiding deliverability issues.
Technical article
Documentation from RFC says that mail clients are able to block file types that are deemed unsafe. PDFs are a commonly targetted file type.
18 Dec 2022 - RFC
Technical article
Documentation from Google Sender Guidelines highlights the importance of aligning your sending domain with your DKIM and SPF records. Although it does not directly mention PDFs, using a custom domain helps build trust, which can positively impact deliverability when linking to PDFs or other external content.
23 May 2022 - Google Sender Guidelines
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