diff --git a/compiler/reporting/src/report.rs b/compiler/reporting/src/report.rs
index 89331eb685..2df5637ceb 100644
--- a/compiler/reporting/src/report.rs
+++ b/compiler/reporting/src/report.rs
@@ -425,7 +425,12 @@ pub fn can_problem<'b>(
                 alloc.reflow(" alias definition:"),
             ]),
             alloc.region(variable_region),
-            alloc.reflow("Roc does not allow phantom type parameters!"),
+            alloc.reflow("Roc does not allow unused type parameters!"),
+            // TODO add link to this guide section
+            alloc.hint().append(alloc.reflow(
+                "If you want an unused type parameter (a so-called \"phantom type\"), \
+                read the guide section on phantom data.",
+            )),
         ]),
         Problem::DuplicateRecordFieldValue {
             field_name,
diff --git a/compiler/reporting/tests/test_reporting.rs b/compiler/reporting/tests/test_reporting.rs
index 76abd42a60..c9823edb3d 100644
--- a/compiler/reporting/tests/test_reporting.rs
+++ b/compiler/reporting/tests/test_reporting.rs
@@ -2663,7 +2663,10 @@ mod test_reporting {
                 1 ┆  Foo a : [ Foo ]
                   ┆      ^
 
-                Roc does not allow phantom type parameters!
+                Roc does not allow unused type parameters!
+
+                Hint: If you want an unused type parameter (a so-called "phantom
+                type"), read the guide section on phantom data.
                 "#
             ),
         )