diff --git a/changelogs/client_server/newsfragments/3530.clarification b/changelogs/client_server/newsfragments/3530.clarification
new file mode 100644
index 00000000..450740ea
--- /dev/null
+++ b/changelogs/client_server/newsfragments/3530.clarification
@@ -0,0 +1 @@
+Add `403 M_FORBIDDEN` error code to `/profile/{userId}` as per [MSC3550](https://github.com/matrix-org/matrix-doc/pull/3550).
diff --git a/data/api/client-server/profile.yaml b/data/api/client-server/profile.yaml
index e0a4c50d..e8bdc4de 100644
--- a/data/api/client-server/profile.yaml
+++ b/data/api/client-server/profile.yaml
@@ -211,7 +211,24 @@ paths:
               displayname:
                 type: string
                 description: The user's display name if they have set one, otherwise not present.
+        403:
+          x-addedInMatrixVersion: "1.2"
+          description: The server is unwilling to disclose whether the user exists and/or has profile information.
+          examples:
+            application/json: {
+              "errcode": "M_FORBIDDEN",
+              "error": "Profile lookup over federation is disabled on this homeserver"
+            }
+          schema:
+            "$ref": "definitions/errors/error.yaml"
         404:
           description: There is no profile information for this user or this user does not exist.
+          examples:
+            application/json: {
+              "errcode": "M_NOT_FOUND",
+              "error": "Profile not found"
+            }
+          schema:
+            "$ref": "definitions/errors/error.yaml"
       tags:
         - User data