Delivering to Gmail
Gmail is a challenge for even the best senders these days.
With the recent Gmail changes there isn’t any clear fix to getting open rates or inbox delivery back up. Some of it depends on what is causing Gmail to filter the mail. Changing subject lines, from name, from address may get mail back to the inbox in the short term, but it only works until the filters catch up.
What I am seeing, across a number of clients, is that Gmail is doing a lot of content reputation and that content reputation gets spread across senders of that content. That means you want to look at who is sending any mail on your behalf (mentioning your domain or pointing at your website) and their practices. If they have poor practices, then it can reflect badly on you and result in filtering.
From what I’ve seen, these are very deliberate filtering decisions by Google. And it’s making mail a lot harder for many, many senders. But I think it is, unfortunately, the new reality.