Short answer: Build your email list only with people who ask to join, and confirm each address with a click before your first newsletter. Gmail and Yahoo ask for both in their sender guidelines. People who asked are less likely to report you as spam, and fewer reports keep more of your email out of the spam folder.
What Gmail and Yahoo ask of a mailing list
Gmail says that if you manage mailing lists, you should send email only to people who want to get messages from you. Those people are less likely to report your messages as spam. When a domain’s messages are often reported, its future messages are more likely to be marked as spam. Over time, the reports can lower the domain’s reputation.
| Practice | Gmail | Yahoo |
|---|---|---|
| Ask before you add | Make sure recipients opt in; avoid sign-up boxes checked by default | Don’t subscribe people with a box checked automatically |
| Confirm the address | Recipients confirm their address before the first subscription message | Send an email that asks them to click to confirm |
| Never buy addresses | Don’t purchase email addresses from other companies | Don’t purchase mailing lists |
| Make leaving easy | One-click unsubscribe, honored within 48 hours | One-click unsubscribe and a visible link, processed within 2 days |
| Keep the list clean | Unsubscribe addresses with multiple bounces; consider removing people who don’t open | Remove invalid recipients promptly; reconfirm inactive subscribers |
Our summary of Gmail Help and Yahoo Sender Hub, read November 6, 2026.
Gmail counts any email sent to a list that people can unsubscribe from as a subscription message, newsletters and marketing messages included. Password resets, purchase receipts and one-time passwords are transactional, and Gmail asks you to send them from a different address than your newsletters.
These are the inboxes’ rules. What United States law asks of every marketing email is in our CAN-SPAM Act guide.
What your sign-up form should say
Yahoo asks you to set expectations when people subscribe: what mail to expect, how often you will send it and what it will look like. It also asks you to honor the frequency people signed up for, so a weekly or monthly newsletter doesn’t turn into a daily one.
Leave the consent box unchecked. Gmail says to avoid opt-in forms that are checked by default, and notes that some countries and regions restrict automatic opt-in.
How double opt-in works
Google calls it double consent: after someone enters an email address on your website or app, they confirm it before you send them subscription messages. Yahoo describes the same step as an email that asks the new subscriber to click to confirm.
Yahoo says the click keeps out people who signed up by accident or were signed up maliciously, along with fake addresses and most robots. It also cuts the invalid addresses that bounce. What to send after someone confirms, such as a welcome series, is in our drip campaign guide.
How to build your email list
- Add a sign-up form where customers already reach you, such as your website or your booking page.
- Say on the form what you will send and how often.
- Leave the consent box unchecked so each person chooses to join.
- Send a confirmation email and add the address only after the click.
- Start with a low volume to your most engaged subscribers and raise it slowly.
- Put a visible unsubscribe link and one-click unsubscribe in every newsletter.
- Remove addresses that bounce several times, and ask inactive subscribers whether they want to stay.
What to leave out of your list
Don’t buy addresses. Gmail says not to purchase email addresses from other companies, and Yahoo says not to purchase mailing lists. Gmail adds that people who didn’t sign up might mark your messages as spam, and that future messages to them will be marked as spam.
Phone numbers for text messages follow their own consent rules, which our SMS marketing guide covers.
How to keep your list clean
Gmail asks you to periodically confirm that recipients want to stay subscribed, and to consider unsubscribing people who don’t open or read your messages. Among its other unsubscribe options, it lists unsubscribing recipients who have multiple bounced messages automatically.
Yahoo says to monitor hard and soft bounces as well as inactive recipients, and to remove invalid recipients promptly. What platforms charge as your list grows is in our article on what email marketing costs.
How spam reports affect your list
Gmail asks senders to keep the spam rate in Postmaster Tools below 0.10% and to avoid ever reaching 0.30%. A high spam rate leads to more of your messages being classified as spam, and improvements can take time to show.
The rest of Gmail’s and Yahoo’s sender rules, authentication included, are in our guide on why emails go to spam.
Before you send to your list
- Everyone on the list asked to join.
- Each new address was confirmed with a click.
- The consent box on your form starts unchecked.
- Every newsletter has a visible unsubscribe link and one-click unsubscribe.
- Addresses with several bounces are off the list.
- Your spam rate in Postmaster Tools is below 0.10%.
RememberAsk before you add, confirm each address, send what you promised and let people leave with one click. Gmail and Yahoo ask for all of it.
Our email and SMS service writes to your customers twice a month in the language they speak, and we never use bought or rented lists. Write to us on WhatsApp or through the form.
Quick answers about building an email list
What is double opt-in?
It’s a sign-up where the new subscriber confirms the email address, usually with a click in an email you send when they join. Google calls it double consent and asks for it before the first subscription message. Yahoo recommends the same step.
Can I buy an email list?
Gmail says not to purchase email addresses from other companies, and Yahoo says not to purchase mailing lists. Gmail adds that people who didn’t sign up might mark your messages as spam, and that future messages to them will be marked as spam.
How often should I email my list?
As often as you said you would when people signed up. Yahoo asks senders to tell new subscribers how often mail will arrive, and not to start sending daily emails to subscribers of a weekly or monthly mailing.
What should I do with subscribers who never open my emails?
Gmail suggests periodically confirming that recipients want to stay subscribed, and considering unsubscribing those who don’t open or read your messages. Yahoo suggests sending inactive subscribers a reconfirmation email from time to time.
I run more than one list. How should I send them?
Gmail asks you to identify each subscription list, with a readable name in the List-id header of every message or with a From address of its own. It also asks you to send newsletters and transactional email, such as receipts, from different addresses.
Sources
All read on November 6, 2026. Gmail Help: Email sender guidelines. Email subscription guidelines for senders. Yahoo Sender Hub: Sender Best Practices.