Skip to content
Blog

Mailto and SMS links: the syntax, with examples

How to write mailto links with a subject, body, cc and line breaks, and sms links with a pre-filled message, so they work in Gmail, Outlook, iPhone and Android.

The Liite team4 min read

A "Request a quote" button that opens an email with the subject already filled in. A "Text us to book" link that opens Messages with your number and a first line ready to send. Both are plain links with a special start: mailto: and sms:.

They're simple, but the details trip people up: line breaks that turn into odd characters, a subject that stops at the first &, a body that doesn't appear on one phone. Here's the syntax that works.

Mailto links

The simplest mailto link is just an address:

mailto:hello@example.com

Add more by putting a ? after the address and joining the extras with &:

mailto:hello@example.com?subject=Quote%20request&body=Hi%2C%20I'd%20like%20a%20quote%20for

The parts you can use:

  • subject: the subject line.
  • body: the text of the email.
  • cc and bcc: extra recipients.
  • More than one recipient: separate addresses with commas, like mailto:sam@example.com,priya@example.com.

In HTML it's an ordinary link:

<a href="mailto:hello@example.com?subject=Quote%20request">Request a quote</a>

Encode everything after the address

Everything after the ? has to be URL-encoded, or mail apps get confused. The ones that cause trouble:

  • Spaces become %20. Don't use +: some mail apps show it as a plus sign.
  • Line breaks become %0D%0A. Gmail, Outlook and Apple Mail all read that as a new line.
  • & in your text becomes %26, or the subject or body stops there.
  • ? becomes %3F, and # becomes %23.
  • Commas can stay as they are in most apps, but %2C is safest.

So a two-line body that says "Hi," and then "I'd like to book." becomes:

body=Hi%2C%0D%0AI'd%20like%20to%20book.

Typing this by hand is fiddly. Our mailto link generator does the encoding, checks the addresses, and gives you the link, an HTML snippet and a QR code.

Mailto pitfalls

  • No default mail app. On a shared or work computer, clicking a mailto link may do nothing, or open an app nobody uses. Show the address as text next to the link so people can copy it.
  • Long bodies get cut off. Some browsers and mail apps cut links at around 2,000 characters. Keep templates short.
  • Spam. An email address in a public page can be read by bots that collect addresses. A contact form avoids that.

SMS links

An sms link opens the Messages app with your number filled in:

sms:+447700900123

Add a message with ?body=:

sms:+447700900123?body=Hi%2C%20I'd%20like%20to%20book%20a%20table

The same encoding rules apply: %20 for spaces, %0D%0A for line breaks. And in HTML:

<a href="sms:+447700900123?body=Hi%2C%20I'd%20like%20to%20book">Text us</a>

Our SMS link generator builds the link, the HTML and a QR code for print.

SMS on iPhone, Android and desktop

  • Use ?body=. Older guides say iPhones need &body= instead. Current iPhones and Android phones both read ?body=.
  • Include the country code, like +44 or +91, so the link works for people texting from abroad.
  • Stick to one number. Links to several numbers at once aren't handled the same way on iPhone and Android.
  • Desktop is hit and miss. On a laptop, an sms link may do nothing or open a phone-link app. If many visitors use computers, show the number as text too.

Nothing is sent automatically. Both kinds of link only fill in the message; the person still presses send.

QR codes for both

A QR code can carry either kind of link, which is handy on posters, flyers and shop windows. Scanning opens a new email or text, ready to send. The SMS generator uses the SMSTO: format that most phone cameras understand. Print the code large enough to scan from where people stand, and test it with a couple of phones first.

If your customers prefer WhatsApp to texting, the same idea works with a wa.me link. Our WhatsApp link generator makes one with a pre-filled message.

Every way to reach you, on one page

Most people have a favourite way to get in touch, and it's rarely the same one. A Liite page at liite.co/yourname can put an email button, a call button and your WhatsApp link side by side, with a count of how many people tap each one.

If you'd rather not show your email address at all, add a Form block instead. Messages arrive in your inbox, and bots never see your address.

Build a link with the mailto link generator or the SMS link generator, or make your free page and give people every way to reach you.