diff --git a/stripe/src/main/java/com/stripe/android/CustomerSession.java b/stripe/src/main/java/com/stripe/android/CustomerSession.java
index 482a05421f4..076b77b3f9d 100644
--- a/stripe/src/main/java/com/stripe/android/CustomerSession.java
+++ b/stripe/src/main/java/com/stripe/android/CustomerSession.java
@@ -17,8 +17,6 @@
 import com.stripe.android.model.ShippingInformation;
 import com.stripe.android.model.Source;
 
-import java.lang.ref.Reference;
-import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Calendar;
@@ -79,10 +77,10 @@ public class CustomerSession
     @Nullable private Customer mCustomer;
     private long mCustomerCacheTime;
     @Nullable private Context mContext;
-    @NonNull private final Map<String, WeakReference<CustomerRetrievalListener>>
-            mCustomerRetrievalListenerRefs = new HashMap<>();
-    @NonNull private final Map<String, WeakReference<SourceRetrievalListener>>
-            mSourceRetrievalListenerRefs = new HashMap<>();
+    @NonNull private final Map<String, CustomerRetrievalListener> mCustomerRetrievalListeners =
+            new HashMap<>();
+    @NonNull private final Map<String, SourceRetrievalListener> mSourceRetrievalListeners =
+            new HashMap<>();
 
     @NonNull private final EphemeralKeyManager mEphemeralKeyManager;
     @NonNull private final Handler mUiThreadHandler;
@@ -134,8 +132,8 @@ public static void endCustomerSession() {
     @VisibleForTesting
     static void clearInstance() {
         if (mInstance != null) {
-            mInstance.mCustomerRetrievalListenerRefs.clear();
-            mInstance.mSourceRetrievalListenerRefs.clear();
+            mInstance.mCustomerRetrievalListeners.clear();
+            mInstance.mSourceRetrievalListeners.clear();
         }
         cancelCallbacks();
         setInstance(null);
@@ -202,7 +200,7 @@ public void retrieveCurrentCustomer(@NonNull CustomerRetrievalListener listener)
             mCustomer = null;
 
             final String operationId = UUID.randomUUID().toString();
-            mCustomerRetrievalListenerRefs.put(operationId, new WeakReference<>(listener));
+            mCustomerRetrievalListeners.put(operationId, listener);
             mEphemeralKeyManager.retrieveEphemeralKey(operationId, null, null);
         }
     }
@@ -217,7 +215,7 @@ public void updateCurrentCustomer(@NonNull CustomerRetrievalListener listener) {
         mCustomer = null;
 
         final String operationId = UUID.randomUUID().toString();
-        mCustomerRetrievalListenerRefs.put(operationId, new WeakReference<>(listener));
+        mCustomerRetrievalListeners.put(operationId, listener);
         mEphemeralKeyManager.retrieveEphemeralKey(operationId, null, null);
     }
 
@@ -256,7 +254,7 @@ public void addCustomerSource(
 
         final String operationId = UUID.randomUUID().toString();
         if (listener != null) {
-            mSourceRetrievalListenerRefs.put(operationId, new WeakReference<>(listener));
+            mSourceRetrievalListeners.put(operationId, listener);
         }
         mEphemeralKeyManager.retrieveEphemeralKey(operationId, ACTION_ADD_SOURCE, arguments);
     }
@@ -278,7 +276,7 @@ public void deleteCustomerSource(
 
         final String operationId = UUID.randomUUID().toString();
         if (listener != null) {
-            mSourceRetrievalListenerRefs.put(operationId, new WeakReference<>(listener));
+            mSourceRetrievalListeners.put(operationId, listener);
         }
         mEphemeralKeyManager.retrieveEphemeralKey(operationId, ACTION_DELETE_SOURCE, arguments);
     }
@@ -319,7 +317,7 @@ public void setCustomerDefaultSource(
 
         final String operationId = UUID.randomUUID().toString();
         if (listener != null) {
-            mCustomerRetrievalListenerRefs.put(operationId, new WeakReference<>(listener));
+            mCustomerRetrievalListeners.put(operationId, listener);
         }
         mEphemeralKeyManager.retrieveEphemeralKey(operationId, ACTION_SET_DEFAULT_SOURCE,
                 arguments);
@@ -629,16 +627,15 @@ public void handleMessage(@NonNull Message msg) {
     private void handleRetrievalError(@Nullable String operationId,
                                       @NonNull StripeException exception,
                                       int errorType) {
-        final WeakReference<? extends RetrievalListener> listenerRef;
+        final RetrievalListener listener;
         if (errorType == SOURCE_ERROR) {
-            listenerRef = mSourceRetrievalListenerRefs.remove(operationId);
+            listener = mSourceRetrievalListeners.remove(operationId);
         } else if (errorType == CUSTOMER_ERROR) {
-            listenerRef = mCustomerRetrievalListenerRefs.remove(operationId);
+            listener = mCustomerRetrievalListeners.remove(operationId);
         } else {
-            listenerRef = null;
+            listener = null;
         }
 
-        final RetrievalListener listener = listenerRef != null ? listenerRef.get() : null;
         if (listener != null) {
             final int errorCode = exception.getStatusCode() == null
                     ? 400
@@ -758,16 +755,12 @@ private void sendErrorIntent(@NonNull StripeException exception) {
 
     @Nullable
     private CustomerRetrievalListener getCustomerRetrievalListener(@Nullable String operationId) {
-        final Reference<CustomerRetrievalListener> listenerRef =
-                mCustomerRetrievalListenerRefs.remove(operationId);
-        return listenerRef != null ? listenerRef.get() : null;
+        return mCustomerRetrievalListeners.remove(operationId);
     }
 
     @Nullable
     private SourceRetrievalListener getSourceRetrievalListener(@Nullable String operationId) {
-        final Reference<SourceRetrievalListener> listenerRef =
-                mSourceRetrievalListenerRefs.remove(operationId);
-        return listenerRef != null ? listenerRef.get() : null;
+        return mSourceRetrievalListeners.remove(operationId);
     }
 
     public interface CustomerRetrievalListener extends RetrievalListener {
diff --git a/stripe/src/main/java/com/stripe/android/Stripe.java b/stripe/src/main/java/com/stripe/android/Stripe.java
index 8d540f51358..1d3dc24ab2c 100644
--- a/stripe/src/main/java/com/stripe/android/Stripe.java
+++ b/stripe/src/main/java/com/stripe/android/Stripe.java
@@ -947,7 +947,7 @@ private static class CreateSourceTask extends AsyncTask<Void, Void, ResponseWrap
         @NonNull private final SourceParams mSourceParams;
         @NonNull private final String mPublishableKey;
         @Nullable private final String mStripeAccount;
-        @NonNull private final WeakReference<SourceCallback> mSourceCallbackRef;
+        @NonNull private final SourceCallback mSourceCallback;
 
         CreateSourceTask(@NonNull Context context,
                          @NonNull StripeApiHandler apiHandler,
@@ -960,7 +960,7 @@ private static class CreateSourceTask extends AsyncTask<Void, Void, ResponseWrap
             mSourceParams = sourceParams;
             mPublishableKey = publishableKey;
             mStripeAccount = stripeAccount;
-            mSourceCallbackRef = new WeakReference<>(sourceCallback);
+            mSourceCallback = sourceCallback;
         }
 
         @Override
@@ -981,13 +981,10 @@ protected ResponseWrapper doInBackground(Void... params) {
 
         @Override
         protected void onPostExecute(@NonNull ResponseWrapper responseWrapper) {
-            final SourceCallback sourceCallback = mSourceCallbackRef.get();
-            if (sourceCallback != null) {
-                if (responseWrapper.source != null) {
-                    sourceCallback.onSuccess(responseWrapper.source);
-                } else if (responseWrapper.error != null) {
-                    sourceCallback.onError(responseWrapper.error);
-                }
+            if (responseWrapper.source != null) {
+                mSourceCallback.onSuccess(responseWrapper.source);
+            } else if (responseWrapper.error != null) {
+                mSourceCallback.onError(responseWrapper.error);
             }
         }
     }
@@ -999,7 +996,7 @@ private static class CreateTokenTask extends AsyncTask<Void, Void, ResponseWrapp
         @NonNull private final String mPublishableKey;
         @Nullable private final String mStripeAccount;
         @NonNull @Token.TokenType private final String mTokenType;
-        @NonNull private final WeakReference<TokenCallback> mCallbackRef;
+        @NonNull private final TokenCallback mCallback;
         @Nullable private final StripeApiHandler.LoggingResponseListener mLoggingResponseListener;
 
         CreateTokenTask(@NonNull Context context,
@@ -1008,7 +1005,7 @@ private static class CreateTokenTask extends AsyncTask<Void, Void, ResponseWrapp
                 @NonNull final String publishableKey,
                 @Nullable final String stripeAccount,
                 @NonNull @Token.TokenType final String tokenType,
-                @Nullable final TokenCallback callback,
+                @NonNull final TokenCallback callback,
                 @Nullable final StripeApiHandler.LoggingResponseListener loggingResponseListener) {
             mContextRef = new WeakReference<>(context);
             mApiHandler = apiHandler;
@@ -1017,7 +1014,7 @@ private static class CreateTokenTask extends AsyncTask<Void, Void, ResponseWrapp
             mStripeAccount = stripeAccount;
             mTokenType = tokenType;
             mLoggingResponseListener = loggingResponseListener;
-            mCallbackRef = new WeakReference<>(callback);
+            mCallback = callback;
         }
 
         @Override
@@ -1043,16 +1040,13 @@ protected void onPostExecute(@NonNull ResponseWrapper result) {
         }
 
         private void tokenTaskPostExecution(@NonNull ResponseWrapper result) {
-            final TokenCallback callback = mCallbackRef.get();
-            if (callback != null) {
-                if (result.token != null) {
-                    callback.onSuccess(result.token);
-                } else if (result.error != null) {
-                    callback.onError(result.error);
-                } else {
-                    callback.onError(new RuntimeException("Somehow got neither a token response or"
-                            + " an error response"));
-                }
+            if (result.token != null) {
+                mCallback.onSuccess(result.token);
+            } else if (result.error != null) {
+                mCallback.onError(result.error);
+            } else {
+                mCallback.onError(new RuntimeException(
+                        "Somehow got neither a token response or an error response"));
             }
         }
     }