Newsletter checklist: what to check before sending

Why check before sending

A mistake in a newsletter reaches every reader at once: a broken link, an empty preview, an image without text, a missing unsubscribe link. Your sending service may check some of this, but not all of it. A fixed checklist takes a few minutes and catches most problems before they reach the inbox.

The parts of an email

An email is more than what you see in the editor. The inbox first shows the sender, the subject and a preview text. Then come the content, the links and the footer. In the background there can be a plain-text version and header lines that mail apps read.

Subject and preview text

• Put the important words first. Where a subject is cut depends on the mail app, the device and the font. On a phone it is often around 40 characters, on a desktop more. Treat this as guidance, not as a rule.
• Write your own preview text, also called preheader. Without one, the inbox shows the first text in the email, often a line like 'View in browser'.
• Let the preview text add something to the subject instead of repeating it.
• Avoid words in capital letters and rows of exclamation marks. Readers see them as pushy, and some spam filters weigh them.

Sender

• Use a sender name and address that readers recognise, the same for every issue.
• Make sure replies arrive somewhere. A reply address that nobody reads loses questions and complaints.
• Put your sender details in the footer, such as company name and postal address. Which details are required depends on your country and the kind of email, so check what applies to you.

Unsubscribe link

Every newsletter needs a visible, working way to unsubscribe. Put the link in the footer with a clear text such as 'Unsubscribe from this newsletter', and test it before each send.

• The link leads straight to the unsubscribe step, without a login.
• One click or one confirmation is enough. Do not ask for the email address again if the link already knows it.
• Do not hide the link in tiny or pale text. Readers who cannot find it often use the spam button instead.

Images and alt text

• Give every image that carries information an alt text that says what it shows or means.
• For a linked image or a button made of an image, the alt text names the destination or the action, such as 'Shop the autumn collection', not 'Banner'.
• Mark purely decorative images with an empty alt attribute (alt="") so that screen readers skip them.
• Do not put the main message only into an image. WCAG asks for real text instead of images of text wherever the technology allows it. Logos are an exception.

More on writing alt text is in our guide on alt text.

Text, images and size

Some mail apps do not load images until the reader allows it. An email that consists mainly of images then shows empty boxes, and the preview has no text. Keep the most important content as text and use images to support it. Keep the HTML lean as well: some mail apps cut off very long messages, and with them the footer with the unsubscribe link.

Link texts

• Say where the link goes: 'See the opening hours' instead of 'Click here'. The purpose of a link should be clear from its text, or from its text together with the surrounding sentence (WCAG 2.4.4).
• Use https for every link.
• If a link shows an address as its text, it should lead to exactly that address.
• Check the tracking parameters: they should be the ones you intended.

Plain-text part

Many sending services add a plain-text version of the email. Some mail apps and readers show only this part. Read it once: it should contain the whole message, readable links and the unsubscribe link, not just a note that the email cannot be displayed.

What to fix first

Not every point is equally important or equally quick to fix. The matrix shows our assessment, not a measurement.

The short checklist

1. 1Subject: important words first, no capital letters for emphasis.
2. 2Preview text: your own, adds to the subject.
3. 3Sender: recognisable name, working reply address, sender details in the footer.
4. 4Unsubscribe: visible, works without a login, tested.
5. 5Images: alt text for content, empty alt for decoration, main message as text.
6. 6Links: clear texts, https, the intended tracking.
7. 7Plain text: complete and readable.
8. 8Test send: to yourself, on a phone and a desktop, in light and dark mode.

Work with Do4U

The tool Newsletter check reads your newsletter before you send it. You paste the HTML or choose a saved .html or .eml file. The code counts the length of the subject and the preview text and shows guidance for phone and desktop. It flags capital letters, many exclamation marks and words that some spam filters weigh, looks for the unsubscribe link and sender details, finds images without alt text, compares text and images and measures the size of the HTML. Every link is listed with its text, tracking parameters and problems such as http or 'click here'. With an .eml file it also checks the plain-text part and the List-Unsubscribe header. The AI then suggests subject lines with a preview text, and the code drops suggestions that are too long or contain a figure that is not in your email.

Do4U never opens your links and sends nothing. It finds hints, you check and decide. It does not check how your email is sent, for example SPF, DKIM or DMARC, and it does not judge which legal rules apply to you.