diff --git a/crates/ruma-common/CHANGELOG.md b/crates/ruma-common/CHANGELOG.md
index bc382893..2357317d 100644
--- a/crates/ruma-common/CHANGELOG.md
+++ b/crates/ruma-common/CHANGELOG.md
@@ -33,6 +33,8 @@ Breaking changes:
 * Make `SimplePushRule` and associated types generic over the expected type of the `rule_id`
 * Deduplicate and group relation structs in `events::relation`:
   * Move relation structs under `events::room::message` to `events::relation`
+  * Move common relation structs under `events::room::encrypted` to `events::relation` and remove
+    duplicate types
 
 Improvements:
 
diff --git a/crates/ruma-common/src/events/enums.rs b/crates/ruma-common/src/events/enums.rs
index d27c9414..d6419935 100644
--- a/crates/ruma-common/src/events/enums.rs
+++ b/crates/ruma-common/src/events/enums.rs
@@ -8,8 +8,9 @@ use super::{
     Redact, Relations,
 };
 use crate::{
-    serde::from_raw_json_value, EventId, MilliSecondsSinceUnixEpoch, OwnedRoomId, RoomId,
-    RoomVersionId, TransactionId, UserId,
+    events::relation::{Annotation, Reference},
+    serde::from_raw_json_value,
+    EventId, MilliSecondsSinceUnixEpoch, OwnedRoomId, RoomId, RoomVersionId, TransactionId, UserId,
 };
 
 event_enum! {
@@ -326,7 +327,7 @@ impl AnyMessageLikeEventContent {
             | Self::KeyVerificationMac(KeyVerificationMacEventContent { relates_to, .. })
             | Self::KeyVerificationDone(KeyVerificationDoneEventContent { relates_to, .. }) => {
                 let key::verification::Relation { event_id } = relates_to;
-                Some(encrypted::Relation::Reference(encrypted::Reference {
+                Some(encrypted::Relation::Reference(Reference {
                     event_id: event_id.clone(),
                 }))
             }
@@ -335,7 +336,7 @@ impl AnyMessageLikeEventContent {
                 use super::reaction;
 
                 let reaction::Relation { event_id, key } = &ev.relates_to;
-                Some(encrypted::Relation::Annotation(encrypted::Annotation {
+                Some(encrypted::Relation::Annotation(Annotation {
                     event_id: event_id.clone(),
                     key: key.clone(),
                 }))
@@ -364,9 +365,7 @@ impl AnyMessageLikeEventContent {
             Self::PollResponse(PollResponseEventContent { relates_to, .. })
             | Self::PollEnd(PollEndEventContent { relates_to, .. }) => {
                 let super::poll::ReferenceRelation { event_id } = relates_to;
-                Some(encrypted::Relation::Reference(encrypted::Reference {
-                    event_id: event_id.clone(),
-                }))
+                Some(encrypted::Relation::Reference(Reference { event_id: event_id.clone() }))
             }
             #[cfg(feature = "unstable-msc3381")]
             Self::PollStart(_) => None,
diff --git a/crates/ruma-common/src/events/relation.rs b/crates/ruma-common/src/events/relation.rs
index ff368956..c1af79aa 100644
--- a/crates/ruma-common/src/events/relation.rs
+++ b/crates/ruma-common/src/events/relation.rs
@@ -30,6 +30,28 @@ impl InReplyTo {
     }
 }
 
+/// An [annotation] for an event.
+///
+/// [annotation]: https://github.com/matrix-org/matrix-spec-proposals/pull/2677
+#[derive(Clone, Debug, Deserialize, Serialize)]
+#[cfg(feature = "unstable-msc2677")]
+#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
+pub struct Annotation {
+    /// The event that is being annotated.
+    pub event_id: OwnedEventId,
+
+    /// The annotation.
+    pub key: String,
+}
+
+#[cfg(feature = "unstable-msc2677")]
+impl Annotation {
+    /// Creates a new `Annotation` with the given event ID and key.
+    pub fn new(event_id: OwnedEventId, key: String) -> Self {
+        Self { event_id, key }
+    }
+}
+
 /// Summary of all annotations to an event with the given key and type.
 #[derive(Clone, Debug, Deserialize, PartialEq, Eq, Serialize)]
 #[cfg(feature = "unstable-msc2677")]
@@ -206,6 +228,23 @@ impl BundledThread {
     }
 }
 
+/// A [reference] to another event.
+///
+/// [reference]: https://spec.matrix.org/v1.5/client-server-api/#reference-relations
+#[derive(Clone, Debug, Deserialize, Serialize)]
+#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
+pub struct Reference {
+    /// The ID of the event being referenced.
+    pub event_id: OwnedEventId,
+}
+
+impl Reference {
+    /// Creates a new `Reference` with the given event ID.
+    pub fn new(event_id: OwnedEventId) -> Self {
+        Self { event_id }
+    }
+}
+
 /// A bundled reference.
 #[derive(Clone, Debug, Deserialize, Serialize)]
 #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
diff --git a/crates/ruma-common/src/events/room/encrypted.rs b/crates/ruma-common/src/events/room/encrypted.rs
index 3f3a5d4f..d399951b 100644
--- a/crates/ruma-common/src/events/room/encrypted.rs
+++ b/crates/ruma-common/src/events/room/encrypted.rs
@@ -9,7 +9,12 @@ use ruma_macros::EventContent;
 use serde::{Deserialize, Serialize};
 
 use super::message;
-use crate::{events::relation::InReplyTo, OwnedDeviceId, OwnedEventId};
+#[cfg(feature = "unstable-msc2677")]
+use crate::events::relation::Annotation;
+use crate::{
+    events::relation::{InReplyTo, Reference, Thread},
+    OwnedDeviceId, OwnedEventId,
+};
 
 mod relation_serde;
 
@@ -149,77 +154,6 @@ impl Replacement {
     }
 }
 
-/// A reference to another event.
-#[derive(Clone, Debug, Deserialize, Serialize)]
-#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
-pub struct Reference {
-    /// The event we are referencing.
-    pub event_id: OwnedEventId,
-}
-
-impl Reference {
-    /// Creates a new `Reference` with the given event ID.
-    pub fn new(event_id: OwnedEventId) -> Self {
-        Self { event_id }
-    }
-}
-
-/// An annotation for an event.
-#[derive(Clone, Debug, Deserialize, Serialize)]
-#[cfg(feature = "unstable-msc2677")]
-#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
-pub struct Annotation {
-    /// The event that is being annotated.
-    pub event_id: OwnedEventId,
-
-    /// The annotation.
-    pub key: String,
-}
-
-#[cfg(feature = "unstable-msc2677")]
-impl Annotation {
-    /// Creates a new `Annotation` with the given event ID and key.
-    pub fn new(event_id: OwnedEventId, key: String) -> Self {
-        Self { event_id, key }
-    }
-}
-
-/// A thread relation for an event.
-#[derive(Clone, Debug, Deserialize, Serialize)]
-#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
-pub struct Thread {
-    /// The ID of the root message in the thread.
-    pub event_id: OwnedEventId,
-
-    /// A reply relation.
-    ///
-    /// If this event is a reply and belongs to a thread, this points to the message that is being
-    /// replied to, and `is_falling_back` must be set to `false`.
-    ///
-    /// If this event is not a reply, this is used as a fallback mechanism for clients that do not
-    /// support threads. This should point to the latest message-like event in the thread and
-    /// `is_falling_back` must be set to `true`.
-    pub in_reply_to: InReplyTo,
-
-    /// Whether the `m.in_reply_to` field is a fallback for older clients or a real reply in a
-    /// thread.
-    pub is_falling_back: bool,
-}
-
-impl Thread {
-    /// Convenience method to create a regular `Thread` with the given event ID and latest
-    /// message-like event ID.
-    pub fn plain(event_id: OwnedEventId, latest_event_id: OwnedEventId) -> Self {
-        Self { event_id, in_reply_to: InReplyTo::new(latest_event_id), is_falling_back: false }
-    }
-
-    /// Convenience method to create a reply `Thread` with the given event ID and replied-to event
-    /// ID.
-    pub fn reply(event_id: OwnedEventId, reply_to_event_id: OwnedEventId) -> Self {
-        Self { event_id, in_reply_to: InReplyTo::new(reply_to_event_id), is_falling_back: true }
-    }
-}
-
 /// The content of an `m.room.encrypted` event using the `m.olm.v1.curve25519-aes-sha2` algorithm.
 #[derive(Clone, Debug, Serialize, Deserialize)]
 #[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
diff --git a/crates/ruma-common/tests/events/encrypted.rs b/crates/ruma-common/tests/events/encrypted.rs
index e1f5de4c..578e7a3a 100644
--- a/crates/ruma-common/tests/events/encrypted.rs
+++ b/crates/ruma-common/tests/events/encrypted.rs
@@ -2,10 +2,10 @@ use assert_matches::assert_matches;
 use ruma_common::{
     device_id, event_id,
     events::{
-        relation::InReplyTo,
+        relation::{InReplyTo, Reference, Thread},
         room::encrypted::{
-            EncryptedEventScheme, MegolmV1AesSha2ContentInit, Reference, Relation, Replacement,
-            RoomEncryptedEventContent, Thread,
+            EncryptedEventScheme, MegolmV1AesSha2ContentInit, Relation, Replacement,
+            RoomEncryptedEventContent,
         },
     },
 };
@@ -328,6 +328,7 @@ fn content_thread_serialization() {
             "m.relates_to": {
                 "rel_type": "m.thread",
                 "event_id": "$thread_root",
+                "is_falling_back": true,
                 "m.in_reply_to": {
                     "event_id": "$prev_event",
                 },
@@ -387,7 +388,7 @@ fn content_thread_deserialization() {
 #[test]
 #[cfg(feature = "unstable-msc2677")]
 fn content_annotation_serialization() {
-    use ruma_common::events::room::encrypted::Annotation;
+    use ruma_common::events::relation::Annotation;
 
     let content = RoomEncryptedEventContent::new(
         encrypted_scheme(),