CustomerGauge works hard to ensure that its own email sending domain has a high reputation, as this is important in ensuring that survey invitations arrive in the inbox of intended B2B recipients.


Equally, CustomerGauge will assist our clients who want to send from their own (sub)domain and, of course, still obtain a good inbox placement.


Specifically, CustomerGauge will:

  • Advise the client's IT department on how to set up the appropriate DNS records (SPF, DKIM, DMARC).
  • Provide a high-reputation, fixed sending IP.

But note that when using a 'Custom Sending Domain' the client themselves are responsible for the reputation of their own subdomain.


However, even with correct DNS declarations and good (sub)domain and IP reputations, inbox placement is not guaranteed as every receiving organization has its own tooling and policies designed to protect employees from unwanted emails. Spam filters are often configured aggressively and may block unexpected correspondence, regardless of the positive reputation of the sending domain.


If you hear that your intended survey recipients are not receiving email invites, the first step is to ask the receiving organization to add your sending domain to their whitelist. This is typically handled by their IT department via the corporate anti-spam filter. If that’s not an option, encourage individual recipients to check their spam folders and mark your survey invitations as 'Safe' or 'Not Spam'. When multiple recipients do this, many spam filtering systems will learn that your emails are trusted and adjust their filtering behavior accordingly.


If the problem persists, it may be necessary to review the survey invitation content itself, as spam filters often weigh content as heavily as technical settings. 


Best practices for avoiding content-related spam triggers include:

  • Avoiding "spammy" phrases like “Act Now”, “Free!!!”, “Click Here”, or excessive use of all caps and exclamation marks.
  • Keeping formatting simple and professional, avoiding large red fonts, garish colors, or overly promotional language.
  • Using a balanced text-to-image ratio: too many images or image-only emails are often flagged as suspicious.
  • Making unsubscribe links visible and not hidden or obscured — this builds trust and is often required for compliance.
  • Ensuring all embedded links use reputable domains and are relevant — avoid URL shorteners or domains with low trust scores.
  • Crafting a clear subject line with no misleading content or clickbait phrasing.
  • Personalizing the email where possible, using recipient names or account-specific context, as generic messaging is more likely to be filtered.
  • Testing your email using spam-check tools (such as Mail-Tester or GlockApps) before sending large campaigns, to catch potential triggers.


By combining good technical setup, careful monitoring of bounce/spam metrics, and thoughtful content creation, you significantly increase the likelihood of successful inbox placement.