diff --git a/homeassistant/components/whois/diagnostics.py b/homeassistant/components/whois/diagnostics.py
new file mode 100644
index 00000000000..19b3822e55c
--- /dev/null
+++ b/homeassistant/components/whois/diagnostics.py
@@ -0,0 +1,27 @@
+"""Diagnostics support for Whois."""
+from __future__ import annotations
+
+from typing import Any
+
+from whois import Domain
+
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers.update_coordinator import DataUpdateCoordinator
+
+from .const import DOMAIN
+
+
+async def async_get_config_entry_diagnostics(
+    hass: HomeAssistant, entry: ConfigEntry
+) -> dict[str, Any]:
+    """Return diagnostics for a config entry."""
+    coordinator: DataUpdateCoordinator[Domain] = hass.data[DOMAIN][entry.entry_id]
+    return {
+        "creation_date": coordinator.data.creation_date,
+        "expiration_date": coordinator.data.expiration_date,
+        "last_updated": coordinator.data.last_updated,
+        "status": coordinator.data.status,
+        "statuses": coordinator.data.statuses,
+        "dnssec": coordinator.data.dnssec,
+    }