diff --git a/bookwyrm/activitypub/base_activity.py b/bookwyrm/activitypub/base_activity.py
index efc9d8da2..b995788c3 100644
--- a/bookwyrm/activitypub/base_activity.py
+++ b/bookwyrm/activitypub/base_activity.py
@@ -250,7 +250,10 @@ class ActivityObject:
                 pass
         data = {k: v for (k, v) in data.items() if v is not None and k not in omit}
         if "@context" not in omit:
-            data["@context"] = "https://www.w3.org/ns/activitystreams"
+            data["@context"] = [
+                "https://www.w3.org/ns/activitystreams",
+                {"Hashtag": "as:Hashtag"},
+            ]
         return data
 
 
diff --git a/bookwyrm/models/user.py b/bookwyrm/models/user.py
index e2671b07f..bc728d5f2 100644
--- a/bookwyrm/models/user.py
+++ b/bookwyrm/models/user.py
@@ -327,6 +327,7 @@ class User(OrderedCollectionPageMixin, AbstractUser):
             "https://w3id.org/security/v1",
             {
                 "manuallyApprovesFollowers": "as:manuallyApprovesFollowers",
+                "Hashtag": "as:Hashtag",
                 "schema": "http://schema.org#",
                 "PropertyValue": "schema:PropertyValue",
                 "value": "schema:value",
diff --git a/bookwyrm/tests/models/test_user_model.py b/bookwyrm/tests/models/test_user_model.py
index 3147f95e3..2e122872d 100644
--- a/bookwyrm/tests/models/test_user_model.py
+++ b/bookwyrm/tests/models/test_user_model.py
@@ -95,6 +95,7 @@ class User(TestCase):
                     "PropertyValue": "schema:PropertyValue",
                     "alsoKnownAs": {"@id": "as:alsoKnownAs", "@type": "@id"},
                     "manuallyApprovesFollowers": "as:manuallyApprovesFollowers",
+                    "Hashtag": "as:Hashtag",
                     "movedTo": {"@id": "as:movedTo", "@type": "@id"},
                     "schema": "http://schema.org#",
                     "value": "schema:value",