The Technical Setup (DKIM, SPF, DMARC)

Before you send a single cold email, you must prove to receiving mail servers (like Gmail) that you are who you say you are. This requires adding three text records to your domain's DNS settings.

1. SPF (Sender Policy Framework)

SPF is a list of IP addresses that are authorized to send email on behalf of your domain. If someone tries to spoof your email address from a server not listed in your SPF record, it gets marked as spam.

2. DKIM (DomainKeys Identified Mail)

DKIM adds a cryptographic signature to every email you send. When the receiver gets the email, they check the signature against your public DNS record. This proves the email was not tampered with in transit.

3. DMARC (Domain-based Message Authentication)

DMARC is the boss. It tells the receiving server what to do if an email fails the SPF or DKIM checks. Setting a DMARC record to p=reject or p=quarantine drastically improves your domain reputation because it proves you care about security.

The Human Rules of Deliverability

Even with perfect technical setup, you will end up in spam if your behavior looks like a spammer. Follow these rules when running outreach:

• Keep volume low: Never send more than 30-50 cold emails per day from a single inbox. If you need to send 500 emails a day, you need 10 different inboxes on different domains.
• Never use your core domain: If your agency website is agency.com, buy tryagency.com or agency.net for outreach. If an outreach domain gets blacklisted, it doesn't take down your main company email.
• No links in the first email: Links (especially tracked links) trigger spam filters. Ask a question and start a conversation first. Send the link in the second email once they reply.
• Personalize everything: If you send the exact same block of text to 200 people, Gmail will fingerprint the text and flag it as spam. Use variables (First Name, Company Name, Industry) to make every email unique.

Deliverability inside Fernly

If you connect your personal or Google Workspace inbox to Fernly, we use your actual email infrastructure to send the messages. This means emails are delivered natively from your account, bypassing the "Send via 3rd party" penalties that platforms like Mailchimp suffer from.

Fernly also randomizes send delays and limits bulk daily sending to protect your domain reputation automatically.