# Write the Subject and Preview Text



> The subject gets attention, and the preview text gives the reader one more reason to open.



- Human page: https://mailrith.com/guides/subject-and-preview

- Markdown page: https://mailrith.com/guides/subject-and-preview.md

- Category: Message

- Reading time: 4 min read

- Related keywords: Write the Subject and Preview Text, Write the Subject and Preview Text guide, Message, Message guide, email sending guide, email marketing guide, email deliverability guide



## AI Agent Notes

- Use this page as plain-language guidance for the specific email sending issue named in the title.

- Preserve the distinction between Mailrith, an email delivery service, DNS, and inbox providers when explaining fixes.

- When a user is running a free tool, pair the tool result with the relevant issue or step section from this guide.



### Write the Subject and Preview Text

The subject gets attention, and the preview text gives the reader one more reason to open.

The subject line is the first promise. The email body must keep that promise. If the subject says one thing and the email says another, subscribers learn not to trust future emails.

Preview text is the short snippet many inboxes show beside or below the subject. Use it to add context. Do not waste it by repeating the subject or leaving default text from the email body.

- Make the subject specific. `Your March account summary is ready` is clearer than `Important update`.
- Avoid tricks that create opens but reduce trust, such as fake replies, false urgency, or misleading offers.
- Use preview text to explain who the email is for, what changed, or why it matters.
- Check subject and preview text on a phone because long text may get cut.
- For recurring newsletters, keep enough consistency that subscribers recognize the format.

## Fix Common Issues
### Missing Subject Line

A content checker found no subject line. A missing or placeholder subject makes the email unclear in the inbox.

1. Write the main reason to open in one short sentence.
2. Avoid vague labels such as `Update` unless the preview explains the value.
3. Match the subject to the actual body content.
4. Send a test email and check how the subject appears on mobile.

### Long Subject Line

A content checker found a subject that may be clipped in mobile inboxes or bury the main point.

1. Move secondary detail into preview text.
2. Put the most important words near the beginning.
3. Remove filler words and repeated context.
4. Send a mobile test and confirm the main promise is visible.

### Overly Loud Subject

A content checker found repeated punctuation or long all-caps text that can make a legitimate campaign look pushy.

1. Rewrite the subject in normal sentence casing.
2. Use one clear promise instead of shouting urgency.
3. Keep punctuation simple.
4. Use truthful deadlines only when there is a real deadline.

### Missing Preview Text

A content checker found no preview text. Inboxes may show random body, footer, or unsubscribe text instead.

1. Write one short preview line that supports the subject.
2. Do not repeat the subject word for word.
3. Use the preview to explain who the email is for, what changed, or why it matters.
4. Send a test email and check the subject plus preview together.



## Related Guides

- [Write the Email Body](https://mailrith.com/guides/write-the-body.md): A good email has one main point, enough context, and one clear next step.

- [Design for Phones First](https://mailrith.com/guides/design-for-phones.md): Most subscribers will scan quickly, so the email must be readable on a small screen.

- [Use Personalization Carefully](https://mailrith.com/guides/personalization.md): Personalization is useful when the data is reliable and awkward when the data is missing or wrong.