Summary
The implementation of GDPR (General Data Protection Regulation) and sudden spikes in email volume have significantly reshaped email deliverability trends. GDPR mandated stricter consent requirements and data privacy, compelling marketers to re-evaluate their list acquisition and management practices. Simultaneously, unplanned or massive surges in email sending volume, often unrelated to GDPR, presented unique challenges, impacting sender reputation and inbox placement. These two factors, one regulatory and the other operational, created a complex environment for email senders.
Key findings
- Initial dip: Around the GDPR enforcement date, many senders experienced an initial drop in deliverability due to high sending volume to old or unengaged lists, combined with re-permissioning campaigns.
- List cleansing: GDPR pushed organizations to clean their email lists, removing inactive or non-consenting subscribers, which ultimately improved long-term engagement and deliverability for compliant senders. This aligns with advice on how email volume affects deliverability.
- ISP response: ISPs (Internet Service Providers) like Gmail and Apple saw varying trends, with some showing rebound and others a continued decline depending on sender behavior post-GDPR and during volume spikes.
- Volume sensitivity: Email service providers (ESPs) and ISPs react negatively to sudden, large email volume spikes, even legitimate ones, often treating them as suspicious activity. This directly relates to impacts of high email volume.
- Post-GDPR normalization: Deliverability tended to improve as senders settled back into their natural or post-GDPR compliant sending volumes and practices.
Key considerations
- Consent management: Ensure explicit consent mechanisms are in place, particularly for new subscribers, to comply with GDPR and similar regulations (for example, GDPR requirements regarding email). This helps maintain a healthy and engaged list.
- List hygiene: Regularly clean email lists to remove inactive subscribers, bounces, and potential spam traps, which can harm sender reputation and deliverability.
- Volume warming: When planning significant increases in email volume, implement proper IP and domain warming strategies to gradually build sender reputation with ISPs. Sudden spikes can lead to emails going to spam.
- Monitoring: Continuously monitor deliverability metrics (inbox placement, bounces, complaints) to quickly identify and address any issues arising from volume changes or list quality problems. For a deeper dive, consider how email deliverability works.
What email marketers say
Email marketers widely discussed the immediate aftermath of GDPR and the associated volume spikes. Many observed a direct correlation between these events and changes in their email deliverability. The prevailing sentiment was that while challenging initially, GDPR ultimately compelled better email marketing practices, particularly around consent and list quality. Volume spikes, however, remained a persistent concern, often leading to temporary deliverability setbacks. Marketers adapted by focusing on permission-based sending and careful volume management.
Key opinions
- Initial negative impact: Many marketers noted a temporary drop in deliverability following GDPR due to increased re-permissioning campaign volume and sending to less engaged segments of old lists. This often led to higher bounce rates and spam complaints.
- Forced clean-up: GDPR acted as a catalyst for marketers to clean their databases and improve data quality, leading to better long-term engagement rates and improved sender reputation.
- Volume spike issues: Irrespective of GDPR, marketers often faced deliverability challenges from sudden, large volume sends, with some seeing delivery rates drop significantly (e.g., to 50% or less) if not properly warmed. You can read more about deliverability pitfalls and best practices.
- Focus on engagement: Post-GDPR, there was an increased emphasis on sending to engaged subscribers, which became a key factor in maintaining good deliverability rather than just list size. This change also affected email marketing as a whole.
Key considerations
- Segmenting lists: Marketers should segment their lists based on engagement levels, avoiding sending high volumes to inactive subscribers. This reduces the risk of hitting spam traps or generating complaints.
- Gradual volume increase: For planned large sends or new IP addresses, a gradual increase in volume is crucial. ISPs monitor sending patterns, and abrupt changes can trigger spam filters and even lead to your IP getting on a blacklist or blocklist.
- Re-engagement campaigns: Instead of removing inactive subscribers immediately, marketers can attempt re-engagement campaigns to confirm interest, but with careful consideration of volume and potential deliverability impact.
- Post-GDPR adaptation: Adopt GDPR principles of data minimization and purpose limitation beyond legal necessity to foster trust and improve email program health.
Marketer view
Email marketer from Email Geeks observes that their central thesis is that deliverability experienced a dip around the time of GDPR enforcement, primarily due to a massive increase in email volume and senders mailing to outdated or old subscriber lists. However, they anticipate that deliverability should improve as senders revert to their regular or post-GDPR compliant sending volumes, indicating a temporary disruption rather than a permanent decline.
Marketer view
Marketer from Business News Daily suggests that by investing in email marketing campaigns and diligently adhering to regulations such as GDPR, businesses should observe a positive impact on their email metrics, including an increase in click-through rates and overall engagement. This indicates that compliance, while initially challenging, can lead to a more effective and responsive email program.
What the experts say
Deliverability experts provided nuanced perspectives on the data surrounding GDPR and volume spikes. While acknowledging the initial disruption, they often cautioned against oversimplifying the trends, pointing out that different mailbox providers reacted differently. Experts consistently emphasized the underlying principles of good sender reputation and the long-term benefits of compliance and managed sending volume, regardless of regulatory changes or market events.
Key opinions
- Data interpretation: Experts sometimes questioned interpretations of raw deliverability data, noting that general trends might not apply uniformly across all ISPs, and individual mailbox provider behaviors (like Gmail rebounding vs. Microsoft/AOL decline) need careful analysis.
- Volume spike impact: There was a general consensus among experts that sudden volume spikes are indeed unfavorable to ESPs and ISPs, regardless of the reason. This underlines the importance of consistent sending patterns.
- Long-term benefits: Despite initial challenges, experts believed GDPR's push for cleaner data and explicit consent would lead to healthier email ecosystems and improved deliverability in the long run. This is a crucial aspect of GDPR's effect on sender reputation.
- Technical alignment: Experts reiterated the importance of proper email authentication (SPF, DKIM, DMARC) in conjunction with responsible sending volumes, especially when facing new regulations or changes in email behavior. For more on this, check out a simple guide to authentication.
Key considerations
- Detailed data analysis: Rely on granular data to understand deliverability trends specific to each mailbox provider, rather than broad generalizations.
- Proactive volume management: Plan email campaigns to avoid sharp, unannounced increases in sending volume, which can negatively impact sender reputation and lead to emails getting blocklisted (or blacklisted).
- Reputation building: Focus on consistent, permission-based sending to cultivate a strong, positive sender reputation, which provides resilience against external factors like regulatory changes or market shifts.
- Adaptability: Maintain flexibility in email strategies to adapt to evolving regulations, ISP filtering mechanisms, and user engagement patterns. This includes staying informed on new rules and higher standards.
Expert view
Expert from Email Geeks (steve589) raises concerns about the interpretation of 250ok's data, suggesting that the trendlines added may not fully support the initial assertions. They point out that Gmail's data indicates increased or rebounding deliverability, while Microsoft and AOL show a pattern of long-term decline that does not align with the stated trend. They conclude that Apple's data might support the case, but not necessarily the specific trendline drawn.
Expert view
Expert from Spam Resource highlights that email deliverability is not a static concept but rather an ongoing process influenced by sender reputation, list hygiene, and content relevance. They often advise that even with perfect authentication, poor sending practices like sudden volume spikes or low engagement can lead to filtering, emphasizing that ISPs prioritize recipient experience above all else.
What the documentation says
Official documentation and research often underscore the foundational principles of email deliverability, emphasizing that compliance with regulations and adherence to best practices for sending volume are critical. GDPR documentation highlights consent, transparency, and data minimization. Deliverability guides from major ISPs and industry bodies stress the importance of sender reputation, which is influenced by sending volume, consistency, and recipient engagement. These sources collectively confirm that both regulatory adherence and careful volume management are intertwined for optimal inbox placement.
Key findings
- GDPR consent: Documentation confirms that GDPR mandates explicit, informed consent for processing personal data, including email addresses for marketing, which directly impacts list building and management. More details can be found on GDPR's view on email.
- Data quality: Regulatory documents emphasize the need for accurate and up-to-date data, aligning with deliverability best practices that prioritize clean, engaged subscriber lists to avoid bounces and complaints.
- Sender reputation: ISP documentation consistently highlights sender reputation as paramount, which is built on consistent sending volume, low complaint rates, and high engagement, penalizing sudden, uncharacteristic volume spikes. This impacts understanding domain reputation.
- Throttling: Mailbox providers' postmaster guidelines often detail how they may temporarily throttle or block emails from senders exhibiting unusual volume patterns until their sending behavior normalizes.
Key considerations
- Compliance as a foundation: View GDPR and similar privacy regulations not just as legal obligations, but as opportunities to strengthen recipient trust and improve email program health, which positively impacts deliverability.
- Volume consistency: Implement technical solutions and processes to ensure consistent email sending volume, avoiding large, abrupt increases that can trigger ISP filters or blocklists.
- Engagement signals: Prioritize recipient engagement metrics (opens, clicks, replies) over raw sending volume, as these are key signals ISPs use to determine inbox placement. Learn more about why deliverability can drop despite low spam.
- Authentication standards: Ensure full compliance with email authentication standards like SPF, DKIM, and DMARC, as these are foundational for establishing trust with mailbox providers and are often prerequisites for high volume sending.
Technical article
Documentation from GDPR.eu explains that the General Data Protection Regulation mandates organizations to safeguard personal data in all its forms, including email addresses. It clarifies that GDPR significantly alters the rules governing consent, requiring explicit and unambiguous agreement from individuals for data processing. Furthermore, it strengthens individuals' privacy rights, giving them more control over their personal information and how it is used in marketing communications, including email.
Technical article
Documentation from Mailmodo defines email deliverability as the critical metric that quantifies the number of emails successfully reaching a subscriber's inbox, rather than being diverted to junk or spam folders. This definition underscores that true deliverability extends beyond simple delivery to the server, focusing instead on actual inbox placement, which is influenced by a multitude of factors including sender reputation and email volume.
Related resources
15 resources
Related pages
How does GDPR affect email deliverability and sender reputation?
Why do emails go to spam, and how does high sending frequency affect deliverability?
What are the observed impacts and repercussions of high email volume during peak sending events?
What impact did GDPR have on email marketing?
How do email volume and volume fluctuations affect deliverability and sender reputation?
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