A mailto: QR code opens a pre-filled email compose window the moment someone scans it. No typing an address, no copy-pasting - the message is ready to send in under three seconds. This guide shows you exactly how to create one, what each field does, and where to use it.
What Is a mailto: QR Code?
A mailto: QR code encodes a mailto: URI - the same standard used by every email link on the web (defined in RFC 6068). When scanned, iOS and Android automatically open the device's default email app with the fields you specified already filled in.
The URI format looks like this:
mailto:[email protected]?subject=Newsletter%20Signup&body=I%20want%20to%20subscribe
You can pre-fill the to address, subject line, and body text. The cc and bcc fields also work but are rarely needed for QR code use cases.
How to Create a QR Code for Email
- Go to the URL QR code generator
- Paste your full mailto: link in the URL field. Example:
mailto:[email protected]?subject=Quote%20Request - Click Generate
- Download as SVG for print or PNG for digital use
- Test by scanning with your phone - the email app should open immediately with all fields filled
If you only need to share your email address (no pre-filled subject or body), simply use mailto:[email protected] as the URL.
When to Pre-Fill the Subject Line
A pre-filled subject line is the most useful part of a mailto: QR code for business use. It lets you:
- Track responses by campaign - use a unique subject per flyer or event ("Trade Show Booth 12 Enquiry")
- Route emails automatically - most email clients support rules based on subject keywords
- Reduce friction - the person scanning does not have to think about what to type
Keep subjects short. Anything over 60 characters gets cut off on most mobile email clients.
Real-World Uses for Email QR Codes
| Use case | Pre-fill fields | Where to print |
|---|---|---|
| Newsletter signup | Subject: "Subscribe me" | Flyers, packaging |
| Quote request | Subject: "Quote Request", body: product name | Product labels, catalogues |
| Event feedback | Subject: "Event Name Feedback" | Table cards, lanyards |
| Customer support | Subject: "Support Request" + order ID | Receipts, packaging inserts |
| Contact card | No subject or body - just the address | Business cards, name badges |
Important Limitations to Know
A mailto: QR code relies on the scanned device having a configured email app. If the person scans it on a device with no email client set up (common on shared or public devices), nothing will happen. For those cases, a plain URL to a contact form is more reliable.
Also, the QR code does not send the email - it only opens the compose screen. The person still needs to tap Send themselves. This is intentional (it is how the mailto: protocol works) and actually better for consent - you are not sending on their behalf.
URL Encoding: Avoid Common Mistakes
Spaces and special characters in your subject or body must be URL-encoded. The most common error is leaving spaces as literal spaces, which breaks the link on some email clients. Replace each space with %20, or use an online URL encoder before pasting into the generator.
Common encodings to remember:
- Space →
%20 - Ampersand →
%26(inside body text only) - Line break →
%0A
Create Your Email QR Code Now
Use the free QR code generator above, paste in your mailto: link, and download. No account required. The code is permanent - it will open your email compose window today, in six months, and in five years.