How should I combine SPF records and what domain should I use with SendinBlue?
Summary
What email marketers say11Marketer opinions
Email marketer from Email Geeks shares that, 'It's possible to set up your organizational domain, as the “domain” in SendinBlue but it’s highly recommended against as you want the sender reputation of your organizational domain to have some separation from the subdomain for marketing.'
Email marketer from Reddit shares that it's recommended to use a subdomain for sending emails with SendinBlue. This helps to separate your sending reputation from your main domain and protects it from potential damage if your email campaigns have issues.
Email marketer from Super User explains that If there is no SPF record or no 'pass' result, many email systems will flag the message as potentially spam or even reject it outright. This can drastically reduce your email deliverability.
Email marketer from SparkPost shares that you should place more 'expensive' lookups (like 'mx' or 'a') near the end of the SPF record, as the system might terminate the evaluation early if the 10-lookup limit is reached.
Email marketer from Email Geeks shares it’s recommended against setting up your organizational domain, <http://lapoppyjewelry.com|lapoppyjewelry.com>, as the “domain” in SendinBlue. It's better to use a subdomain to separate sender reputation. He also recommends deleting the SPF for SendinBlue and leaving the one for Google if the root domain is entered as the domain in SendinBlue.
Email marketer from GMass shares that common mistakes during SPF setup are having multiple SPF records and not using the correct syntax. Also notes that using too many lookups can lead to failures.
Email marketer from Email Geeks explains that combining SPF records with `v=spf1 a mx include:<http://spf.mtasv.net|spf.mtasv.net> include:<http://spf.sendinblue.com|spf.sendinblue.com> ~all` is sufficient and that having two SPF records will result in evaluation errors.
Email marketer from DeskRabbit shares that an SPF record must contain no more than 255 characters. This can present a problem, especially if you send emails from several different locations.
Email marketer from EasyDMARC shares that SPF flattening is a technique to reduce the number of DNS lookups in your SPF record. This helps to avoid exceeding the 10-lookup limit and ensures proper SPF authentication.
Email marketer from Mailjet shares that SPF records are essential for preventing email spoofing and improving deliverability. They emphasize the importance of creating a valid SPF record that accurately reflects all sending sources for your domain.
Email marketer from ServerFault explains that you should not have multiple SPF records for the same domain. Instead, you should combine all the necessary includes into a single SPF record. They provide an example of how to combine multiple includes.
What the experts say3Expert opinions
Expert from Spam Resource answers that if you use multiple email service providers, such as Sendinblue, you must ensure all are included within a single SPF record for your domain. This involves using 'include:' mechanisms for each provider, rather than creating separate SPF records, which is invalid.
Expert from Email Geeks explains that you can drop the MX mechanism and that one MX is sufficient but unnecessary. Also clarifies SPF authenticates the envelope from/return path/bounce domain, not the domain seen in the mail client.
Expert from Word to the Wise explains that when using ESPs, you should be putting SPF records in for a subdomain, not the bare domain, to isolate reputation.
What the documentation says4Technical articles
Documentation from RFC specification answers that an SPF record should include all authorized sources which are able to send mail on behalf of the domain, including any third-party services such as email marketing platforms.
Documentation from SendinBlue explains that you need to authenticate your domain to improve deliverability. This involves adding SPF and DKIM records to your domain's DNS settings. They provide specific instructions for generating and adding these records within the SendinBlue platform.
Documentation from Google Workspace Admin Help answers that you can add or update your domain's SPF record in your domain settings. It details the steps and syntax for creating an SPF record that includes Google Workspace.
Documentation from dmarcian explains that SPF records have a lookup limit of 10 DNS lookups. Exceeding this limit can cause SPF authentication to fail. They recommend using includes wisely and flattening your SPF record if necessary.