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    Understand email deliverability

    Course overview
    Lesson
    2 min read

    Understand the role of email inbox providers

    Inbox providers like Gmail and Yahoo play a huge role in determining whether or not your email messages reach a subscriber’s inbox. Learn how they work to protect consumers, and what you can do to keep a good reputation with these providers.

    Who are email inbox providers?

    As a marketer, you’re familiar with email service provider (ESP) softwares like Klaviyo that help bulk senders manage their mass email communications. But have you ever stopped to think about the third-parties who control the inboxes of your recipients? We refer to these service providers as email inbox providers. Some of the most popular providers include:

    • Gmail
    • Yahoo
    • Outlook
    • iCloud Mail

    Each service provider has their own rules and set of standards that they use to determine which email messages should be directed to the spam folder or blocked entirely. The whole purpose of the spam folder is to quarantine messages that are potentially harmful and prevent recipients from engaging with those messages. For this reason, inbox providers are intentionally vague about the criteria they use for spam filtering so they can avoid providing bad actors with too much information.

    Understand bulk sender requirements for Gmail and Yahoo

    Gmail and Yahoo, two of the most popular inbox providers, have taken the lead in the industry on tightening up requirements for bulk senders. Google defines a “bulk sender” as domains who send messages to more than 5,000 Gmail users on any given day (this includes messages sent from your domain across the entire internet, like system notifications from your website, transactional messages, and marketing messages). Yahoo's definition is more vague, simply stating that a bulk sender is anyone sending a "significant volume" of mail.

    Unless you are on a free Klaviyo account, or have a very small customer base, you likely fall into the category of "bulk sender".

    As a bulk sender, your messages are subject to a higher level of scrutiny because you have the ability to reach so many people. The sender requirements that you must meet in order to reach Gmail and Yahoo inboxes are:

    • Authenticate your domain
    • Set up a DMARC policy
    • Align your sender address to your domain
    • Offer one-click unsubscribe
    • Keep spam complaints low

    We will cover each of these topics in detail throughout the rest of this certificate. By the end of this certificate, you will know exactly how to ensure you are compliant with bulk sender requirements for both Gmail and Yahoo.

    Understand the role of email inbox providers