Why do SendGrid transactional emails go to spam but campaign emails go to inbox?

Marketer from Email Geeks shares he's seen this happen a lot (I assume you mean gmail). Not sure exactly what it is but gmail is fantastic at fingerprinting certain sends. Could be the headers, could be the content, could be the cadence, but they can tell the difference.

Email marketer from Gmass shares that not having a Double Opt-In strategy can hurt your email deliverability and domain authority. Double opt-in can show inbox providers that your contacts actually want to receive emails from you, greatly reducing your spam complaints and boosting sender reputation.

Email marketer from Mailgun Blog explains that transactional emails often suffer from poor IP reputation because they are sent from new IPs or shared IPs with other senders who might not have the best practices. Campaign emails, on the other hand, might benefit from a dedicated IP with a better reputation due to consistent sending practices.

Email marketer from Email Hippo shares that using a shared IP address for transactional emails can negatively impact deliverability. If other senders on the same IP have poor sending practices, it can affect the reputation of all senders on that IP. Consider using a dedicated IP address for transactional emails.

Email marketer from ActiveCampaign explains that poor email list hygiene practices affects deliverability. Ensure you are regularly cleaning your email list and pruning any inactive or unengaged contacts to prevent spam complaints.

Email marketer from Stack Overflow answers that transactional emails are often sent in low volumes compared to campaign emails. Sudden bursts of transactional emails, especially from new IPs, can trigger spam filters. Gradually increase the sending volume of transactional emails to establish a good reputation.

Email marketer from Email on Acid Blog explains that transactional emails might have different header information than campaign emails. Discrepancies in headers, such as missing or incorrect 'Message-ID' or 'Date' fields, can negatively impact deliverability.

Email marketer from Reddit shares that transactional emails are often shorter and contain different content compared to campaign emails. This can trigger spam filters that analyze content patterns. For example, transactional emails might contain specific keywords or phrases related to order confirmations or password resets, which spam filters might flag if they appear suspicious.

Email marketer from Litmus shares that failing to properly warm up the IP address for transactional emails can lead to spam placement. Transactional emails sent from new IPs without a warm-up period are more likely to be flagged as spam.

Expert from Word to the Wise responds that inbox providers treat emails differently depending on the configurations applied. Some configurations may be missing on some emails, such as authentication or feedback loops. This creates a problem when the inbox providers treat your emails more favorably when they can determine they are legitimate through configurations.

Expert from Email Geeks suggests looking at authentication settings.

Expert from Email Geeks shares if you're sending yourself lots of tests, you might have also trained your own inbox by deleting them without engaging with them. Or you've trained the mailbox provider that these are spam by sending too many of them. Check the performance of those types of emails within SendGrid compared to your campaigns sent through SendGrid.

Expert from Spam Resource explains that differences in engagement metrics between transactional and campaign emails can impact deliverability. Transactional emails often have lower open and click-through rates, leading mailbox providers to view them less favorably.

Documentation from RFC explains that a lack of feedback loops for transactional emails can lead to deliverability issues. Feedback loops allow email providers to notify senders when recipients mark their emails as spam. Implementing feedback loops helps improve sender reputation and deliverability.

Documentation from Microsoft explains that if your sender reputation is low, then Microsoft is more likely to filter your emails straight to the junk folder or block your email altogether. Use Microsoft's Smart Network Data Services (SNDS) to track your reputation.

Documentation from SendGrid explains that transactional emails might lack proper authentication (SPF, DKIM, DMARC) configurations compared to campaign emails. Missing or misconfigured authentication can cause email providers to flag transactional emails as suspicious, leading to spam placement.

Documentation from Google Postmaster Tools explains that if the spam rate for transactional emails is higher than campaign emails, Gmail is more likely to classify transactional emails as spam. Monitor your spam rate using Postmaster Tools to ensure that it stays below the threshold.