diff --git a/homeassistant/components/trmnl/config_flow.py b/homeassistant/components/trmnl/config_flow.py
index d3ec0d1ca87..828bc1a3ad4 100644
--- a/homeassistant/components/trmnl/config_flow.py
+++ b/homeassistant/components/trmnl/config_flow.py
@@ -22,6 +22,8 @@ from .const import DOMAIN, LOGGER
 
 STEP_USER_SCHEMA = vol.Schema({vol.Required(CONF_API_KEY): str})
 
+TRMNL_ACCOUNT_URL = "https://trmnl.com/account"
+
 
 class TRMNLConfigFlow(ConfigFlow, domain=DOMAIN):
     """TRMNL config flow."""
@@ -66,6 +68,7 @@ class TRMNLConfigFlow(ConfigFlow, domain=DOMAIN):
             step_id="user",
             data_schema=STEP_USER_SCHEMA,
             errors=errors,
+            description_placeholders={"account_url": TRMNL_ACCOUNT_URL},
         )
 
     async def async_step_reauth(
diff --git a/homeassistant/components/trmnl/strings.json b/homeassistant/components/trmnl/strings.json
index ea278acacc2..250a1195157 100644
--- a/homeassistant/components/trmnl/strings.json
+++ b/homeassistant/components/trmnl/strings.json
@@ -21,7 +21,8 @@
         },
         "data_description": {
           "api_key": "The API key for your TRMNL account."
-        }
+        },
+        "description": "You can find your API key on [your TRMNL account page]({account_url})."
       }
     }
   },