Summary
When sending emails through an email service provider (ESP) like Klaviyo, it's common to see SPF, DKIM, and DMARC authentication passing in email headers even if you haven't explicitly added these records to your own domain's DNS. This occurs because Klaviyo (or any ESP) performs the authentication on its own shared sending domains, or on subdomains it provisions for you. While this allows messages to pass initial authentication checks, it often means your primary domain reputation isn't fully leveraged, and DMARC alignment might fail. This can impact deliverability and brand trust, especially with evolving sender requirements from major mailbox providers.
Key findings
- Shared domain authentication: Klaviyo authenticates emails on its own shared sending domains (e.g., klaviyomail.com) if you have not set up custom authentication. This ensures that SPF and DKIM pass, but the authentication is tied to Klaviyo's domain, not yours.
- Header visibility: When you view the original email headers, the SPF and DKIM pass results indicate that Klaviyo's sending infrastructure is properly authenticated.
- DMARC alignment: While SPF and DKIM may pass for Klaviyo's domains, your "From" domain (the one recipients see) might not align with the authenticated domain. This DMARC alignment failure can lead to emails going to spam or being rejected, especially with new Google and Yahoo requirements.
- Klaviyo's stance: Klaviyo's official documentation clarifies that for emails sent on their shared sending domains, you don't need to add your own SPF and DKIM records, as they manage this for you.
Key considerations
- Domain reputation impact: Relying solely on shared domain authentication means your brand's domain does not directly benefit from the positive sending reputation, which could impact inbox placement.
- Increased deliverability: To achieve the highest deliverability and comply with modern email standards, setting up custom domain authentication (SPF, DKIM, and DMARC for your domain) is crucial.
- DMARC policy enforcement: Without proper DMARC records and alignment, you miss out on critical reporting and enforcement capabilities that protect your domain from spoofing and phishing.
- Compliance with new requirements: Gmail and Yahoo now require all bulk senders to have a DMARC policy with alignment, even if it's set to p=none. This mandates custom authentication for optimal inbox placement. More details can be found on Klaviyo's blog regarding why DMARC is important.
What email marketers say
Email marketers often encounter this confusion: emails pass authentication checks, yet their own domain lacks the necessary DNS records. This leads to questions about how deliverability is maintained and what steps are needed to ensure robust domain health. The consensus among marketers is a mix of understanding Klaviyo's default behavior and recognizing the growing importance of taking ownership of one's own authentication for long-term success.
Key opinions
- Initial confusion: Many marketers are puzzled when their emails pass SPF, DKIM, and DMARC without them explicitly setting up these records, leading to a false sense of security regarding their authentication setup.
- Reliance on ESP: Some marketers rely entirely on their ESP (like Klaviyo) to handle authentication, trusting the platform's assurances that no additional records are needed from their side.
- Prioritizing inbox placement: While immediate deliverability might seem high, marketers are increasingly concerned about long-term domain health and inbox placement, especially with new authentication requirements.
- Desire for control: There's a strong desire among experienced marketers to have full control over their email authentication (SPF, DKIM, DMARC) to ensure their brand's reputation is directly tied to their sending efforts.
Key considerations
- Understanding shared IPs: Marketers should be aware that using shared IPs and Klaviyo's authentication means their sending reputation is influenced by other Klaviyo users, which can be a double-edged sword.
- Impact of DMARC alignment: Even if SPF and DKIM pass on a shared domain, DMARC alignment is critical for domain-level authentication and preventing spoofing.
- Investigating email headers: Marketers are advised to inspect full email headers to identify which domains are actually passing SPF and DKIM authentication, to understand the true sending path.
- Proactive setup: It's highly recommended for marketers to set up custom SPF, DKIM, and DMARC records for their own domain within Klaviyo to maximize deliverability and comply with new sender rules. This process is detailed in Klaviyo's authentication guides.
Marketer view
Email marketer from Email Geeks inquires about a perplexing situation where emails from their dedicated sending domain appear to pass SPF, DKIM, and DMARC, despite no records being present in their DNS. They highlight that their Klaviyo team stated these records aren't necessary, which seems to contradict standard deliverability practices.
Marketer view
An anonymous marketer from Email Geeks expresses concern about maintaining high deliverability, domain health, and reputation given the unusual authentication behavior they are observing. They seek input on how to ensure optimal performance when their setup seems unconventional.
What the experts say
Experts in email deliverability consistently highlight the technical nuances of how ESPs handle authentication, particularly the distinction between an ESP authenticating on its own behalf versus authenticating on the customer's behalf. The core message is that while shared domain authentication might achieve basic passes, it lacks the full benefits of direct domain alignment and DMARC enforcement, which are increasingly vital for maintaining a strong sender reputation and ensuring long-term inbox placement, especially with evolving industry standards.
Key opinions
- Shared vs. custom authentication: Experts confirm that when a user hasn't configured custom authentication, Klaviyo's systems authenticate emails using Klaviyo's own shared domains.
- Alignment is key: Even if SPF and DKIM pass, if the domain in the Mail From/Return-Path (for SPF) and the d=tag (for DKIM) doesn't align with the domain in the visible 'From' header, DMARC will fail. This is crucial for domain reputation.
- Headers reveal the truth: Analyzing email headers provides definitive proof of which domains are being authenticated for SPF and DKIM, and whether DMARC alignment is passing or failing.
- Full control is superior: While shared authentication may work, experts advocate for brands to implement their own SPF, DKIM, and DMARC records to gain full control over their sending identity and improve deliverability resilience.
Key considerations
- DMARC adoption: The increasing adoption of DMARC by mailbox providers, coupled with new requirements from Google and Yahoo, makes custom DMARC implementation a non-negotiable for serious senders.
- Brand spoofing protection: Without proper DMARC alignment and an enforced policy, your brand remains vulnerable to spoofing and phishing attacks, potentially leading to brand damage and blacklist listings.
- Deliverability best practices: Best practices dictate that brands should always aim to authenticate their emails with their own domains, even when using third-party ESPs. This is central to maximizing email deliverability.
- ESP configuration: While ESPs handle some aspects, users must follow their specific instructions to set up custom authentication. For Klaviyo, this usually involves adding CNAME records that delegate authentication to Klaviyo's systems, enabling alignment.
Expert view
Deliverability expert from Email Geeks clarifies that the authentication observed passing is most likely Klaviyo's own domains, not the user's direct domain, which is a common setup for ESPs when custom authentication isn't in place.
Expert view
Deliverability expert from Email Geeks suggests that Gmail's 'view original' feature is a reliable way to determine exactly which domains are passing authentication checks (SPF and DKIM), providing crucial insight into the actual sending entity.
What the documentation says
Official documentation from Klaviyo and related resources consistently emphasizes the importance of email authentication, whether it's managed by the ESP or by the sender directly. While Klaviyo historically handled authentication for users on shared domains, recent industry changes (like those from Google and Yahoo) necessitate that senders take a more proactive role in setting up their own DMARC, SPF, and DKIM records for optimal deliverability and brand protection. The documentation often provides specific instructions on how to configure these records within their platform.
Key findings
- Klaviyo's default authentication: For senders using Klaviyo's shared sending domain, the platform manages SPF and DKIM authentication automatically, meaning users are not required to add these records to their own DNS.
- DMARC requirement: Klaviyo's documentation, in line with industry best practices and new sender requirements, states that all senders must implement SPF, DKIM, and DMARC records to ensure proper email authentication.
- Custom domain setup: To achieve full authentication alignment with their brand domain, users are instructed to configure custom SPF, DKIM, and DMARC records within their DNS settings, often provided by Klaviyo itself.
- Verification methods: Documentation suggests using authentication information in email headers to verify that SPF, DKIM, and DMARC are passing, providing a method for senders to confirm their setup.
Key considerations
- Aligning domains: DMARC ensures that the domain in the 'From' address aligns with the domains authenticated by SPF and DKIM, a critical step for domain trust and deliverability.
- Importance of DMARC: Klaviyo's blog emphasizes that DMARC is essential for email security, helping to prevent spoofing and ensuring that messages originate from legitimate senders.
- SPF record purpose: SPF specifies which mail servers are authorized to send emails on behalf of your domain, protecting against unauthorized sending.
- New sender requirements: Recent updates from major inbox providers like Gmail and Yahoo necessitate strong authentication, making full SPF, DKIM, and DMARC implementation for your domain a fundamental requirement for bulk senders. For more information, refer to Klaviyo's deliverability guide.
Technical article
Klaviyo Help Center documentation clarifies that when sending emails, you are not required to add your own SPF and DKIM records if you are sending on Klaviyo's shared sending domain. This indicates their system handles default authentication for shared infrastructure.
Technical article
Klaviyo's blog post emphasizes that, in line with industry best practices, all senders must implement SPF, DKIM, and DMARC records. This equips senders with protection against spoofing and enhances deliverability. The documentation confirms that even if it's not strictly necessary for shared domain sending, it is required for optimal performance and security.
Related resources
4 resources
Related pages
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