diff --git a/lib/index.js b/lib/index.js
index b6f5ed0..0bddf4c 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -121,7 +121,7 @@ const changelog =
 const emptyPlugins = []
 /** @type {Readonly<RemarkRehypeOptions>} */
 const emptyRemarkRehypeOptions = {allowDangerousHtml: true}
-const safeProtocol = /^(https?|ircs?|mailto|xmpp)$/i
+const safeProtocol = /^(https?|ircs?|mailto|tel|xmpp)$/i
 
 // Mutable because we `delete` any time it’s used and a message is sent.
 /** @type {ReadonlyArray<Readonly<Deprecation>>} */
diff --git a/test.jsx b/test.jsx
index 1b254db..b4eaaf7 100644
--- a/test.jsx
+++ b/test.jsx
@@ -335,6 +335,13 @@ test('Markdown', async function (t) {
     )
   })
 
+  await t.test('should support a tel', function () {
+    assert.equal(
+      renderToStaticMarkup(<Markdown children="[](tel:+12345678910)" />),
+      '<p><a href="tel:+12345678910"></a></p>'
+    )
+  })
+
   await t.test('should allow an empty URL', function () {
     assert.equal(
       renderToStaticMarkup(<Markdown children="[]()" />),