diff --git a/src/com/github/iusmac/sevensim/telephony/SubscriptionController.java b/src/com/github/iusmac/sevensim/telephony/SubscriptionController.java
index e2bae32..48d7abd 100644
--- a/src/com/github/iusmac/sevensim/telephony/SubscriptionController.java
+++ b/src/com/github/iusmac/sevensim/telephony/SubscriptionController.java
@@ -71,6 +71,9 @@ public void setUiccApplicationsEnabled(final int subId, final boolean enabled) {
             return;
         }
 
+        // Ensure SIM subscription syncing cannot start in parallel during this operation
+        mSubscriptions.mBlockSubscriptionsSyncFlag.set(true);
+
         sub.setSimState(TelephonyUtils.simStateInt(enabled));
         sub.setLastActivatedTime(enabled ? LocalDateTime.now(ZoneId.systemDefault()) :
                 LocalDateTime.MIN);
@@ -79,5 +82,7 @@ public void setUiccApplicationsEnabled(final int subId, final boolean enabled) {
         mSubscriptions.persistSubscription(sub);
 
         mSubManager.setUiccApplicationsEnabled(subId, enabled);
+
+        mSubscriptions.mBlockSubscriptionsSyncFlag.set(false);
     }
 }
diff --git a/src/com/github/iusmac/sevensim/telephony/Subscriptions.java b/src/com/github/iusmac/sevensim/telephony/Subscriptions.java
index 6999717..5899e0c 100644
--- a/src/com/github/iusmac/sevensim/telephony/Subscriptions.java
+++ b/src/com/github/iusmac/sevensim/telephony/Subscriptions.java
@@ -99,6 +99,12 @@ public void onReceive(final Context context, final Intent intent) {
      */
     private final AtomicBoolean mCarrierConfigChangedReceiverRegistered = new AtomicBoolean();
 
+    /**
+     * Atomic flag indicating whether the synchronization of the internal state of all SIM
+     * subscriptions is blocked or not. Use this to ensure atomic SIM subscription state mutations.
+     */
+    final AtomicBoolean mBlockSubscriptionsSyncFlag = new AtomicBoolean();
+
     private final Context mContext;
     protected final Logger mLogger;
     protected final SubscriptionManager mSubscriptionManager;
@@ -295,6 +301,11 @@ public void removeOnSubscriptionsChangedListener(
      */
     @WorkerThread
     public void syncSubscriptions(final LocalDateTime dateTime) {
+        if (mBlockSubscriptionsSyncFlag.get()) {
+            mLogger.w("syncSubscriptions(dateTime=%s) : Operation has been disallowed.", dateTime);
+            return;
+        }
+
         final List<String> removedSubIds = new ArrayList<>(getPersistedUsableSubIds());
         final List<String> usableSubIds = new ArrayList<>();
 
diff --git a/src/com/github/iusmac/sevensim/telephony/TelephonyController.java b/src/com/github/iusmac/sevensim/telephony/TelephonyController.java
index c309bda..27ea610 100644
--- a/src/com/github/iusmac/sevensim/telephony/TelephonyController.java
+++ b/src/com/github/iusmac/sevensim/telephony/TelephonyController.java
@@ -135,6 +135,9 @@ public void setSimState(final int slotIndex, final boolean enabled,
                 return;
             }
 
+            // Ensure SIM subscription syncing cannot start in parallel during this operation
+            mSubscriptions.mBlockSubscriptionsSyncFlag.set(true);
+
             // Keep track of SIM state whenever it's mutated. This will be persisted in a volatile
             // memory, so that we can further restore all relevant data. This because when powering
             // down the SIM is the same as removing it, which means the SIM will completely
@@ -226,6 +229,8 @@ public void setSimState(final int slotIndex, final boolean enabled,
                 }
                 handleOnSetSimPowerStateForSlotFinished(resCode);
             }
+
+            mSubscriptions.mBlockSubscriptionsSyncFlag.set(false);
         }
     }