Definition
Click-to-call is a hyperlink or button in an email that, when tapped on a mobile device, opens the phone app with a phone number already entered. It removes the friction of remembering or manually typing a number, making it especially useful for local businesses, service providers, sales teams and appointment-based companies.
Click-to-call links use the standard telephone URL scheme, typically written as tel:+1234567890. When the recipient clicks on a supported device, the phone app launches and prompts the user to dial the number. On desktop, the link may open a calling app or VoIP service if one is configured.
This CTA format is most effective when the email itself creates urgency or convenience, such as 'Call now to book your appointment' or 'Speak with a specialist today.' It should be used alongside other conversion options, such as landing page links, because not all recipients will want to call.
Best Practices
- Use click-to-call CTAs for mobile-first audiences or high-consideration services.
- Include the phone number in plain text as a fallback for unsupported clients.
- Test the link on iOS and Android devices to ensure it dials correctly.
- Pair click-to-call with a landing page link for recipients who prefer to browse first.
- Track calls generated from email using unique numbers or UTM parameters where possible.
Related Glossary Terms
A/B Testing
A/B testing in email marketing is the practice of sending two variations of an email to a small sample of your list to determine which version performs better before sending the winner to the remaining subscribers.
Abandoned Cart Email
An abandoned cart email is an automated message sent to customers who added items to their online shopping cart but left without completing the purchase. It is one of the highest-converting email types in ecommerce.
Above the Fold in Email
Above the fold in email refers to the content visible to a recipient before they scroll, a critical area for first impressions and primary calls to action.
Accessible CTA (Email)
An accessible CTA is a button or link coded with sufficient colour contrast, visible focus states, descriptive screen-reader text, and a minimum touch target of 44×44 pixels.
Adaptive Design
Adaptive design in email uses predefined layouts that adjust to specific device or client widths, rather than fluidly resizing to every possible screen.
AI-Generated Content in Email
AI-generated content in email is copy, images, code or subject lines produced by artificial intelligence tools to speed up campaign production and testing.
Frequently Asked Questions
Use a tel: link, such as Call us. On mobile devices, this opens the phone app.
It may open a default calling app or VoIP service, but support is limited. Provide a fallback phone number and landing page link.
Use it when a phone call is the fastest or most valuable conversion path, such as booking appointments, requesting quotes or speaking with sales.
Yes, using unique phone numbers, call tracking software, or by linking to a landing page that then triggers the call.
Yes, it is designed for mobile. Make the button large enough to tap and place it where mobile users will see it quickly.