Most newsletters that land in spam have the same few problems. A plain guide to SPF, DKIM, DMARC, list hygiene and warming up a new sending domain.
A client emailed us last spring with a familiar complaint. Their monthly newsletter, which used to get a healthy open rate, had dropped to almost nothing. The content hadn’t changed. The list hadn’t shrunk. The emails were simply going to spam.
It took about a day to find out why, and about two weeks to fix. The causes were the same ones we see almost every time.
Inbox providers are guessing
Gmail, Outlook and the rest don’t read your newsletter and decide whether it’s good. They look at signals: who sent it, whether that sender can prove who they are, and how people reacted to past mail from them.
That’s good news, because most of those signals are under your control. It also means a single weak signal can drag everything else down.
Prove who you are
The first thing we check is authentication. Three DNS records do most of the work:
- SPF lists the servers allowed to send mail for your domain.
- DKIM signs each message, so the receiver can tell it wasn’t changed on the way.
- DMARC tells receivers what to do when the first two fail, and sends you reports about it.
Our client had SPF, but it pointed at an email tool they’d stopped using two years earlier. Their new tool wasn’t in it at all. DKIM was set up for a different subdomain. DMARC didn’t exist.
A minimal DMARC record to start with looks like this:
_dmarc.example.com TXT "v=DMARC1; p=none; rua=mailto:dmarc@example.com"Start with p=none so you only collect reports. Once the reports show everything passing, move to quarantine, then reject.
Clean the list
The second problem was the list itself. It had grown for six years and never been pruned. Thousands of addresses hadn’t opened anything in over a year. Some were abandoned inboxes that providers now use as spam traps.
Sending to people who never engage tells providers your mail isn’t wanted. We removed everyone with no opens or clicks in twelve months, after one last “still interested?” email. The list got smaller. The open rate roughly tripled.
Warm up slowly
When you move to a new sending domain or a new provider, you start with no reputation. Sending fifty thousand emails on the first day looks exactly like a spammer.
We ramp up over two to three weeks, starting with the most engaged readers and adding more each send. It feels slow. It’s much faster than recovering from a bad first impression.
Keep an eye on it
Once things are healthy, a few habits keep them that way:
- Read the DMARC reports, or have a tool summarize them for you.
- Watch bounce and complaint rates after every send.
- Make unsubscribing easy and immediate. A frustrated reader who can’t leave will click “spam” instead.
The short version
Most deliverability problems aren’t mysterious. They’re a stale DNS record, a list nobody has cleaned, or a new domain pushed too hard too soon. Fix those, and your newsletter goes back to where it belongs: in front of the people who asked for it.
That’s the work Beacon does for our clients every month, quietly, so they can get back to writing.
