Advanced tips to improve your email deliverability

These tips are for members who know the basics of deliverability. New to it? Start with How to improve your email deliverability.

Deliverability depends above all on your habits. Five things make the difference:

1. Send from your own authenticated domain.
2. Clean your list regularly of bounced, unsubscribed and inactive contacts.
3. Only email people who agreed to it.
4. Understand the sending pools.
5. Track your statistics.

1. Use your own authenticated domain

Receiving servers filter incoming email. Sending from your own domain, authenticated with SleepPRO™, builds trust with parents and lets servers recognize your domain's reputation. See How to authenticate your domain name for email sending, then contact support to have it checked.

2. Clean your list regularly

Every contact you import must have agreed to hear from you, and know what you will send them. Addresses bought or found online, such as from directories or public social profiles, are not allowed. Accounts which harm the service can have email sending suspended or be blocked.

Clean your list before you import it, and at least once a month after, keeping only parents who open your emails.

Addresses which do not exist: old closed addresses and misspelled ones. Misspelled addresses are removed automatically. Filter by Bounced to find the rest. See How to delete bounced contacts.

Inactive addresses: tag them first. Then either run a re-engagement campaign, which only works well with a segmented list, or delete them. See How to manually clean your email list.

Double opt-in: new subscribers receive an email with a link to confirm. Anyone who does not confirm within 24 hours is removed. This keeps out fake addresses and bots, and confirms each parent truly wants your emails. See How to set up double opt-in.

3. Good email habits

Target your emails. Segment with tags, so each family receives what fits them. Untargeted emails lead to low opens, unsubscribes and spam reports.

Make sender, subject and content match. Filters now check closely whether the sender name, subject and content fit together. If you share ready-made email sequences with others, remind them to keep these three consistent. Never pretend to be another person or company, and use one sender name per account or address. A sender name like "Your bank" is not allowed and may be blocked.

For example, an email from "Your bank" with the subject "You received $200" which then invites people to join a program is misleading. The subject does not match the content, and the sender is not a bank.

No link shorteners. Following Gmail's restrictions, do not use Bitly, TinyURL or similar tools in your emails.

Links instead of attachments. Link to downloadable files rather than attaching them.

Watch for spam words. Filters consider context, frequency, placement and spelling, not only single words.

Make unsubscribing easy. A visible unsubscribe link is better for your deliverability than ignored emails or spam reports.

Sign your emails. Add your name, business name and details in your footer, and your website if you are a company. Some countries, such as Germany, expect this. Keep your links and your sending domain pointing to the same working domain.

4. Sending pools

Senders are grouped into pools, each with its own set of IP addresses. IP reputation is key to deliverability, so good statistics keep you in the best pools.

• Green: excellent statistics.
• Yellow: average statistics.
• Red: poor statistics.
• Quarantine: new senders with poor statistics.
• Grey: new senders, until they have sent at least 500 emails.

The rules:

• Pools are updated every morning.
• You need to be a customer for at least 16 days to leave the new sender pool.
• You stay in a pool at least 14 days before moving.
• You need to send a minimum number of emails in your current pool before moving: grey 500, quarantine 1,000, green 5,000, yellow 5,000, red 5,000.

Emails are checked from your last pool change up to 5 days ago. These 5 days give time to collect bounce rates, spam reports and open rates.

The three numbers to watch:

• Bounce rate: the share of emails rejected by receiving servers, for example fake, closed or blacklisted addresses.
• Spam reports: how many parents marked your email as spam, compared to opens.
• Open rate: opens compared to emails sent.

Thresholds:

• High risk: open rate under 10%, spam reports 0.4% to 1% (at least 6), bounce rate 1.8% to 5% (at least 30).
• Moderate risk: open rate 10% to 20%, spam reports 0.25% to 0.4% (at least 6), bounce rate 0.7% to 1.8% (at least 30).
• Low risk: open rate over 20%, spam reports under 0.25%, bounce rate under 0.7%.
• Quarantine: emails from the last 24 hours are checked, and a sender moves straight to quarantine with spam reports over 1% or a bounce rate over 5%. At least 1,000 emails sent up to 5 days ago are checked.

In quarantine or red? Follow the steps above, and use the guide below to read and fix your statistics.

5. Track your statistics

Accounts are monitored daily. If a number looks abnormally high, email sending is paused for safety, in the interest of all members.

Bounce rate:

• Under 0.5%: fine.
• 0.6% to 1.9%: look for the cause.
• 2% or more: critical. Contact support as soon as possible.

Spam reports:

• Under 0.08%: fine.
• 0.08% to 0.19%: find out why parents report you.
• 0.2% or more: critical. Contact support as soon as possible.

Open rate:

• 20% or more: good.
• 10% to 20%: average.
• Under 10%: clean your list.