diff --git a/changes/45969-list-certificate-templates-null b/changes/45969-list-certificate-templates-null
new file mode 100644
index 0000000000..993d2c7f7e
--- /dev/null
+++ b/changes/45969-list-certificate-templates-null
@@ -0,0 +1 @@
+- Fixed `List certificate templates` API docs: query parameter was incorrectly documented as `fleet` instead of `fleet_id`, causing the parameter to be silently ignored and returning no results.
diff --git a/docs/REST API/rest-api.md b/docs/REST API/rest-api.md
index 8e9ba2fc9d..88d47dc3ae 100644
--- a/docs/REST API/rest-api.md	
+++ b/docs/REST API/rest-api.md	
@@ -936,7 +936,7 @@ List certificate added to Fleet. Currently, they can only be added via GitOps.
 
 | Name      | Type    | In   | Description                                                    |
 | ----------| ------- | ---- | -------------------------------------------------------------- |
-| fleet      | string  | query | _Available in Fleet Premium_. The fleet ID to filter profiles. |
+| fleet_id   | integer | query | _Available in Fleet Premium_. The fleet ID to filter certificate templates. |
 | page      | integer | query | Page number of the results to fetch.                          |
 | per_page  | integer | query | Results per page.                                             |
 | order_key | string  | query | What to order results by. Allowed field is `id`. |
diff --git a/server/datastore/mysql/certificate_templates.go b/server/datastore/mysql/certificate_templates.go
index 70db9d8ead..d803163b05 100644
--- a/server/datastore/mysql/certificate_templates.go
+++ b/server/datastore/mysql/certificate_templates.go
@@ -171,7 +171,7 @@ func (ds *Datastore) GetCertificateTemplatesByTeamID(ctx context.Context, teamID
 		return nil, nil, ctxerr.Wrap(ctx, err, "apply list options")
 	}
 
-	var templates []*fleet.CertificateTemplateResponseSummary
+	templates := []*fleet.CertificateTemplateResponseSummary{}
 	if err := sqlx.SelectContext(ctx, ds.reader(ctx), &templates, stmtPaged, args...); err != nil {
 		return nil, nil, ctxerr.Wrap(ctx, err, "getting certificate_templates by team_id")
 	}
diff --git a/server/datastore/mysql/certificate_templates_test.go b/server/datastore/mysql/certificate_templates_test.go
index bf17a05201..bccd91f44d 100644
--- a/server/datastore/mysql/certificate_templates_test.go
+++ b/server/datastore/mysql/certificate_templates_test.go
@@ -488,6 +488,7 @@ func testGetCertificateTemplatesByTeamID(t *testing.T, ds *Datastore) {
 			func(t *testing.T, ds *Datastore) {
 				templates, _, err := ds.GetCertificateTemplatesByTeamID(ctx, 1, fleet.ListOptions{Page: 0, PerPage: 10})
 				require.NoError(t, err)
+				require.NotNil(t, templates, "expected empty slice, not nil (nil marshals to JSON null)")
 				require.Len(t, templates, 0)
 			},
 		},