diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6e110a03..3bec7f8c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -41,6 +41,9 @@
 * Kitty keyboard protocol:
   - [Report event types](https://sw.kovidgoyal.net/kitty/keyboard-protocol/#report-events)
     (mode `0b10`)
+  - [Report alternate keys](https://sw.kovidgoyal.net/kitty/keyboard-protocol/#report-alternates)
+    (mode `0b100`, but not that only the _shifted_ key is reported,
+    not the _base layout key_)
   - [Report all keys as escape codes](https://sw.kovidgoyal.net/kitty/keyboard-protocol/#report-all-keys)
     (mode `0b1000`)
   - [Report associated text](https://sw.kovidgoyal.net/kitty/keyboard-protocol/#report-text)
diff --git a/input.c b/input.c
index 0242371a..77818c1a 100644
--- a/input.c
+++ b/input.c
@@ -1156,6 +1156,7 @@ kitty_kbd_protocol(struct seat *seat, struct terminal *term,
 
     const bool disambiguate = flags & KITTY_KBD_DISAMBIGUATE;
     const bool report_events = flags & KITTY_KBD_REPORT_EVENT;
+    const bool report_alternate = flags & KITTY_KBD_REPORT_ALTERNATE;
     const bool report_all_as_escapes = flags & KITTY_KBD_REPORT_ALL;
 
     if (!report_events && released)
@@ -1247,7 +1248,7 @@ emit_escapes:
         encoded_mods |= mods & (1 << seat->kbd.mod_num)   ? (1 << 7) : 0;
     encoded_mods++;
 
-    int key = -1;
+    int key = -1, alternate = -1;
     char final;
 
     switch (sym) {
@@ -1430,6 +1431,8 @@ emit_escapes:
             key = xkb_keysym_to_utf32(sym_to_use);
             if (key == 0)
                 key = sym_to_use;
+            else
+                alternate = xkb_keysym_to_utf32(sym);
         }
 
         final = 'u';
@@ -1460,6 +1463,11 @@ emit_escapes:
         bytes = snprintf(p, left, "\x1b[%u", key);
         p += bytes; left -= bytes;
 
+        if (report_alternate && alternate > 0 && alternate != key) {
+            bytes = snprintf(p, left, ":%u", alternate);
+            p += bytes; left -= bytes;
+        }
+
         if (encoded_mods > 1 || event[0] != '\0' || report_associated_text) {
             bytes = snprintf(p, left, ";%u%s", encoded_mods, event);
             p += bytes; left -= bytes;
diff --git a/terminal.h b/terminal.h
index 394871f6..09b04614 100644
--- a/terminal.h
+++ b/terminal.h
@@ -135,6 +135,7 @@ enum kitty_kbd_flags {
     KITTY_KBD_REPORT_ASSOCIATED = 0x10,
     KITTY_KBD_SUPPORTED = (KITTY_KBD_DISAMBIGUATE |
                            KITTY_KBD_REPORT_EVENT |
+                           KITTY_KBD_REPORT_ALTERNATE |
                            KITTY_KBD_REPORT_ALL |
                            KITTY_KBD_REPORT_ASSOCIATED),
 };