Jim Bennett

Jim Bennett runs several newsletters and builds the templates on One Page Newsletters. His focus is the part of a newsletter readers never see: the code that decides whether an issue looks right in Gmail, Outlook and Apple Mail, whether it survives dark mode, and whether it reaches the inbox at all.

Every template here is tested before it is published: measured for size, checked across email clients and run through inbox placement tests. The blog covers what those tests teach, from authentication and list hygiene to layout, fonts and subject lines.

He writes in plain language for people who send their own newsletter, whether it has two hundred readers or two hundred thousand.

Articles by Jim Bennett

• Custom HTML email templates: which platforms accept themKit, Mailchimp, MailerLite, Brevo, Buttondown, MailCheap, beehiiv and Substack: which accept a custom HTML email template, on which plan, and what they strip.
• Email deliverability: the complete guide for newslettersHow newsletter deliverability works in Gmail, Yahoo and Outlook: authentication, the 2024 sender rules, spam rates, list care and testing.
• Email preheader: what it is and how to write oneWhat an email preheader is, where it appears, how long it can be, how to add a hidden preheader in HTML and how to write one that earns the open.
• Gmail clipped message: why it happens and how to fix itWhy Gmail shows "Message clipped" on newsletters over 102 KB, what gets hidden, how to measure your HTML weight and how to bring it down.
• Newsletter format: the complete guideHow to choose and build a newsletter format: the main types, structure, length, layout, subject and preheader, images, plain text and the technical limits.
• Newsletter subject lines that get openedHow to write newsletter subject lines that get opened without hurting deliverability: clarity, consistency, length, the preheader pair and what to avoid.
• Plain text vs HTML emails: what our tests showPlain text vs HTML emails for newsletters: what each really means, what one same-list comparison showed, and when a designed issue is still the right choice.
• SPF, DKIM and DMARC explained for newsletter writersWhat SPF, DKIM and DMARC do, which records a newsletter needs, how alignment works, and how to check your setup before your next send.