Email Receipt Issues

When you send email invitations to complete a survey using a contact list, there can sometimes be issues which prevent recipients receiving email invitations or the messages being moved into their Junk/SPAM folder.

This can also apply to Email Triggers, Save and Continue mails, and report notifications. 

SPAM is any "unsolicited" email. that-is, email that was not asked for or expected. Now that email is very widely used, there are three scenarios to be aware of:

1) Email spoofing - This is where the sending or receiving email servers are not verifying that the sender is allowed to send email on behalf of a domain. This is much less common today since any good mail server (including SmartSurvey's servers) are configured to correctly be able to verify the sending. If you use your own sending domain e.g., then using DKIM and SPF will ensure that your domain is treated correctly.

2) Genuine SPAM - Someone has illegally obtained email addresses and is sending email that should not have been sent. This is the most likely to be "Marked as spam" by the recipient and can affect any future deliveries from the same email server. Since SmartSurvey shared mail servers across many customers, one customer can affect the reputation of our servers for themselves and other customers. You can only control that you are using email legally and are encouraged to make this clear in the invitation if there is any reason that the recipient might consider it as spam. SmartSurvey includes an opt-out link but if using your own internal mailing list, you are encouraged (and sometimes legally required) to provide an opt-out link.

3) Email that is considered SPAM - this is where the email is legally sent but the user either does not know why they have received it or it looks suspicious. Some people even use the "Mark as spam" as a way of saying, "I am no longer interested in this" so that the sender is considered suspect even though they did nothing illegal. This can be helped by clear and concise messaging (see below) but in general, the email should not be too short or overly long and can include wording like, "If you no longer want to receive these <emails> then please click here to unsubscribe".

Note that phishing is slightly different in-as-much as it can either be in-bulk or more specific and targetted and is to extract data or to make the recipient carry out some kind of illegal action. Normal SPAM, on the other hand, might be sending people to a legitimate business but was simply an unsolicited invitation. To the recipient, they are unlikely to distinguish between the two.

To ensure that emails are sent with the best chance of being delivered, it's important to focus on these elements of the message.

SPAM traps that try and detect this email on behalf of recipients are not an exact science and can vary from provider to provider, so this guidance is only to improve your chances of successful delivery, it can never be guaranteed.

Sending Emails and Domains

Sending with just a verified email but not a sending domain can lead to issues. It is much better to use both a sending domain and an email from that domain. For an explanation, read on...

SmartSurvey allows you to verify an email address to be used as a "from" address in several of the email systems, such as the address book and email triggers. If you use an email and do NOT have an associated sending domain then our system will send on your behalf using one of our own email domains. This can have deliverability issues due to something called DMARC.

For example, if you verify an address such as GMail, your message will be delivered as "From on behalf of". If the from address domain (e.g. has a DMARC record that is set to strict then the receiving service might complain that the message doesn't appear to be genuine and doesn't "align" correctly even if the message is signed with "DKIM". This might cause warning messages to be displayed to the recipient or even for the mail to be put into the spam folder.

This situation is much better if you can purchase/use your own email domain so that we can make everything align correctly. The from address and the DKIM signing key as well as the SPF record will all come from the same domain (the one you verified), and the receiving systems will be much more likely to deliver the email.

Contact List

Low quality contact-lists are the most likely reason for your email invitations to fail delivery and they can cause significant reputational damage to SmartSurvey email servers since invalid email addresses or addresses that are seen as dormant for considerable time are markers that your data is not valid or up-to-date.

  • Ensure your contact list data is valid and up-to-date. If your address books contain lots of old email addresses or those that were obtained in an indirect way, it will increase the chances of people using the "Mark as spam" button, which greatly increases the chance of your messages being blocked.
  • You should proactively review the list to ensure you remain compliant with the Data Protection Act if you are sending to UK Citizens (and are recommended to for others). Specifically, ensure that you are not keeping the data for longer than necessary and that you can prove a legally obtained reason for having those details in the first place.
  • If you are not the entity that the user consented to processing their data, you must be legally permitted to process it and should make it clear in any emails why an email is sent from you rather than the entity you are subcontracted to. For example, "Dear Simon, Example Inc are acting on behalf of Acme Ltd to process any returns. Since you have recently returned an item, we hope that you can spare 2 minutes to tell us how the process went." In any case, you should use personal information to add assurance that you have more than just an email address.

Sender / Reply Email Address  

  • This must be a valid email address for responses to be sent to. You will need to verify the email address before you can send any emails. Note that if you do NOT also verify the domain, emails are sent in a "mangled" way from the system with an address ending with either or, this is because without verifying the domain, the email would otherwise probably fail validation at the recipient's email provider.
  • Verifying the sending domain can also be very helpful. in particular, be aware that for Test email sends, many mail servers will automatically reject mail that is tagged as coming from their own domain that the server knows it did not send. Verifying the domain with DKIM and SPF will resolve this issue.
  • If this is not possible, or if issues persist after doing the above, contact support. We have smartsurvey addresses and a domain that can be used, but we need to activate this for you.


  • Avoid long subjects with mixed numerals and capital letters, as these can be picked up as spam by recipients’ email filters.
  • Try and avoid words and phrases that would commonly be used in Spam emails. Phrases that include urgency such as "complete these as soon as possible" should be avoided.

Message Contents

  • Ensure any images used in the email have alt text.
  • Do not use link shorteners. Real links are much easier for a user to verify and are less likely to be considered SPAM.
  • For email tool survey invitations - Do not remove the [SURVEYLINK] tag. This will automatically be merged with the unique survey link for that respondent so they can be tracked correctly. If you need to add a custom variable to the link, or otherwise control how it's displayed in the email in detail, replace it with [SURVEYLINK_NL]
  • Check that any other URLs used in the email content are complete and load their targeted pages.
  • Try and avoid words and phrases that would commonly be used in Spam or Phishing emails. Phrases that contain too many superlatives like "amazing", "you won't believe" etc. are phrases that are likely to score highly on a SPAM trap.
  • Ensure your message is not too short. For example, if sending to your own staff where you might not need a large introduction, short messages like "Here is the link I mentioned" could trigger a SPAM trap.
  • Try and personalise the email with e.g. "Dear Simon". This makes the message less likely to be detected as a mass mailing and also helps the recipient know that you have their real contact information and haven't just stolen an email address, which reduces the chance of a recipient marking the email as SPAM.
  • It can help, if it is not obvious, to indicate to the recipient why they are receiving the survey link e.g. "Since you recently purchased an item from Acme, we would really appreciate it if you could spare 5 minutes to give us some feedback". This, again, reduces the chance of having your emails marked as SPAM.
  • If SmartSurvey is not your main contact list, you should provide any legally-required opt-out in each message. Although SmartSurvey includes an opt-out for our systems, a recipient will be happier to see e.g. "You can opt-out of any further emails from Acme by clicking this link".

Sending Frequency

  • For survey invitations, the system will send these in batches with a delay between each batch to avoid hitting any rate-limiting mechanisms. This is especially troublesome if you have many contacts that use the same email provider.
  • You should avoid sending too many survey invitations to the same people on the same day. Getting multiple similar emails from the same email address or email server will look suspicious to a SPAM trap.

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