diff --git a/matrix_sdk_crypto/src/user_identity.rs b/matrix_sdk_crypto/src/user_identity.rs
index 4594b6f9..8b154a2f 100644
--- a/matrix_sdk_crypto/src/user_identity.rs
+++ b/matrix_sdk_crypto/src/user_identity.rs
@@ -20,6 +20,7 @@ use std::{
     },
 };
 
+use serde::{Deserialize, Serialize};
 use serde_json::to_value;
 
 use matrix_sdk_common::{
@@ -33,19 +34,19 @@ use crate::{error::SignatureError, verify_json, ReadOnlyDevice};
 ///
 /// Master keys are used to sign other cross signing keys, the self signing and
 /// user signing keys of an user will be signed by their master key.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct MasterPubkey(Arc<CrossSigningKey>);
 
 /// Wrapper for a cross signing key marking it as a self signing key.
 ///
 /// Self signing keys are used to sign the user's own devices.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct SelfSigningPubkey(Arc<CrossSigningKey>);
 
 /// Wrapper for a cross signing key marking it as a user signing key.
 ///
 /// User signing keys are used to sign the master keys of other users.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct UserSigningPubkey(Arc<CrossSigningKey>);
 
 impl PartialEq for MasterPubkey {
@@ -233,7 +234,7 @@ impl SelfSigningPubkey {
 }
 
 /// Enum over the different user identity types we can have.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub enum UserIdentities {
     /// Our own user identity.
     Own(OwnUserIdentity),
@@ -279,7 +280,7 @@ impl PartialEq for UserIdentities {
 /// This is the user identity of a user that isn't our own. Other users will
 /// only contain a master key and a self signing key, meaning that only device
 /// signatures can be checked with this identity.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Deserialize, Serialize)]
 pub struct UserIdentity {
     user_id: Arc<UserId>,
     master_key: MasterPubkey,
@@ -370,7 +371,7 @@ impl UserIdentity {
 ///
 /// This identity can verify other identities as well as devices belonging to
 /// the identity.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Deserialize, Serialize)]
 pub struct OwnUserIdentity {
     user_id: Arc<UserId>,
     master_key: MasterPubkey,