How to bold text in Gmail (body, mobile and subject line)

To bold text in Gmail, select the words in your message body and press Ctrl+B on Windows or Cmd+B on Mac, or click the B in the formatting bar. The subject line is different: Gmail treats it as plain text, so it has no bold option. This guide covers the body, the mobile apps, plain text mode, and the honest workaround for subject lines.

How to bold text in the body of a Gmail message

On a computer, formatting lives in a toolbar at the bottom of the compose window. Bold is a two-step job:

1. Open a new message with Compose.
2. Type your text, then select the words you want heavier.
3. Press Ctrl + B (Windows and Chromebook) or Cmd + B (Mac), or click the B in the formatting bar.

If the bar is hidden, click the Formatting options icon, the letter A with lines under it, at the bottom of the window. The same shortcuts give you italic with Ctrl/Cmd + I and underline with Ctrl/Cmd + U. Pressing the shortcut again on the same selection removes the style.

You can also switch bold on before you type. Press the shortcut, type the phrase, and press it again to turn bold off.

Bold text in the Gmail app on Android and iPhone

The mobile apps also format the body of a message. Type your text, select the words, and open the formatting option that appears with the selection. The exact menu changes between app versions and between Android and iPhone, so if you cannot find it, check Gmail Help for your device or update the app.

If the option is missing entirely, the message may be in plain text mode, which strips all formatting. The next section explains how to check that.

When formatting options are missing: plain text mode

Gmail lets you compose in rich text, which supports bold, italic, colors, lists and links, or in plain text mode, which supports none of them. If the bar is greyed out or the shortcut does nothing, plain text mode is the likely cause.

To change it on a computer, click More options, the three dots at the bottom right of the compose window, and turn Plain text mode off. Formatting you already applied may disappear when you switch to plain text, so turn it off before you write the message rather than after.

Recipients matter too. Some people read email in plain text, and some corporate systems convert messages to it. In those cases your bold simply will not show, so never rely on bold alone to carry a deadline or a warning. Write the date in the sentence as well.

Why you cannot bold a Gmail subject line

Try to bold the subject box and nothing happens, because the subject is a plain-text header field, not a rich-text area. The email standard, RFC 5322, defines the subject as unstructured text, so every mail program treats it as plain. Pasting styled text from a document usually strips the formatting, and no email client offers a bold button for subjects.

So the question for subject lines is not how to turn on bold. It is whether to fake it, and that is a judgment call.

The Unicode workaround for subject lines

There is one way to get bold-looking letters in a subject: use Unicode characters that are drawn bold. They come from the Mathematical Alphanumeric Symbols block, and they look like this: 𝗥𝗲𝗽𝗹𝘆 𝗻𝗲𝗲𝗱𝗲𝗱. Generate them in the bold text generator, copy the result, and paste it into the subject box.

It does work in most modern inboxes, but it comes with trade-offs:

• Deliverability: unusual characters can look odd to spam filters. Test on a small group before a wider send.
• Older or locked-down clients: some show empty boxes instead of the styled letters.
• Screen readers: many read the characters one by one, which is hard on a blind reader.
• Search: searching your inbox for a plain word may not find the styled version.

Our deeper piece on bold email subject lines and Unicode covers the testing steps. If you do use it, style at most one word and keep the sentence readable without it.

Better ways to stand out than bold

Bold in a subject line is a small lever. Most of the click comes from the words themselves. Specific beats decorative:

• Lead with the detail the reader cares about, not your company name.
• Keep the whole line short enough to survive a phone preview. The character counter shows your length as you draft.
• Name a concrete benefit, date or number.
• Match the subject to the first line of the message so nothing feels like a bait switch.

For ready-made phrasing, see our email subject line examples. If you write outreach, the guide to cold emails that get replies and the note on follow-ups after no response cover the message that follows the subject.

Using bold well inside the message

Once you are in the body, restraint pays off. A few habits keep formatting useful:

• One bold phrase per paragraph at most. More than that and nothing stands out.
• Bold the action, not the greeting. Mark the date, the number or the request.
• Do not combine bold, color and underline. Underline can look like a link.
• Keep a plain-text sentence for anything critical. Recipients on plain text will not see the styling.
• Use lists for steps. A numbered list from the toolbar often reads better than bold labels.

If you send templates, paste the finished version into a test message to yourself first and open it on a phone. Copying from a document can carry over fonts and sizes that look different in the recipient's inbox.

Set a default text style so you stop reformatting

If you always want the same look, change the defaults instead of formatting each message. In Gmail on a computer, open Settings, choose See all settings, and find the Default text style section on the General tab. There you can pick the font, size and color that new messages start with. Bold is rarely a good default, since a message that is heavy from the first word gives the reader nothing to scan for, but a consistent font and size can save time.

Pasting text without carrying over old formatting

A common cause of messy emails is pasting from a document or web page and dragging its fonts, sizes and bold along with it. Use the paste-as-plain-text shortcut, Ctrl + Shift + V on Windows or Cmd + Shift + V on Mac, to bring in only the words. Then apply bold yourself where you want it. This keeps the message consistent, and it stops a stray bold sentence from a source page landing in a client email.

Bold in a signature

The signature editor in Gmail settings also supports basic formatting, so you can bold your name or a job title once and reuse it. As with the body, keep it light. A signature that is bold, colored and three sizes at once looks like an advertisement, and plain-text recipients will see none of it, so make sure your name and contact details are readable without the styling.

Quick reference

For a wider look at which apps have real bold and which need a paste, see where bold text works, app by app.