diff --git a/native/account/registration/registration-context-provider.react.js b/native/account/registration/registration-context-provider.react.js
--- a/native/account/registration/registration-context-provider.react.js
+++ b/native/account/registration/registration-context-provider.react.js
@@ -2,9 +2,14 @@
 
 import * as React from 'react';
 
+import { isLoggedIn } from 'lib/selectors/user-selectors.js';
+import type { SIWEBackupSecrets } from 'lib/types/siwe-types';
+
 import { RegistrationContext } from './registration-context.js';
 import { useRegistrationServerCall } from './registration-server-call.js';
 import type { CachedUserSelections } from './registration-types.js';
+import { commCoreModule } from '../../native-modules.js';
+import { useSelector } from '../../redux/redux-utils.js';
 
 const emptyObj: CachedUserSelections = Object.freeze({});
 
@@ -20,6 +25,8 @@
   const setSkipEthereumLoginOnce = React.useCallback((skip: boolean) => {
     baseSetSkipEthereumLoginOnce(skip || undefined);
   }, []);
+  const [siweBackupSecrets, setSIWEBackupSecrets] =
+    React.useState<?SIWEBackupSecrets>(undefined);
 
   const registrationServerCall = useRegistrationServerCall();
   const contextValue = React.useMemo(
@@ -29,14 +36,34 @@
       setCachedSelections,
       skipEthereumLoginOnce,
       setSkipEthereumLoginOnce,
+      siweBackupSecrets,
+      setSIWEBackupSecrets,
     }),
     [
       registrationServerCall,
       cachedSelections,
       skipEthereumLoginOnce,
       setSkipEthereumLoginOnce,
+      siweBackupSecrets,
+      setSIWEBackupSecrets,
     ],
   );
+  const storeLoaded = useSelector(state => state.storeLoaded);
+  const loggedIn = useSelector(isLoggedIn);
+  const lastPersistedBackupSecret = React.useRef<?SIWEBackupSecrets>(undefined);
+
+  React.useEffect(() => {
+    void (async () => {
+      if (!siweBackupSecrets || !storeLoaded || !loggedIn) {
+        return;
+      }
+      if (lastPersistedBackupSecret.current === siweBackupSecrets) {
+        return;
+      }
+      lastPersistedBackupSecret.current = siweBackupSecrets;
+      await commCoreModule.setSIWEBackupSecrets(siweBackupSecrets);
+    })();
+  }, [storeLoaded, siweBackupSecrets, loggedIn]);
 
   return (
     <RegistrationContext.Provider value={contextValue}>
diff --git a/native/account/registration/registration-context.js b/native/account/registration/registration-context.js
--- a/native/account/registration/registration-context.js
+++ b/native/account/registration/registration-context.js
@@ -3,6 +3,7 @@
 import * as React from 'react';
 
 import type { SetState } from 'lib/types/hook-types.js';
+import type { SIWEBackupSecrets } from 'lib/types/siwe-types.js';
 
 import type {
   RegistrationServerCallInput,
@@ -18,6 +19,8 @@
   // skipping the login flow once, so that the user can back out and change it.
   +skipEthereumLoginOnce?: ?true,
   +setSkipEthereumLoginOnce: boolean => void,
+  +siweBackupSecrets?: ?SIWEBackupSecrets,
+  +setSIWEBackupSecrets: SetState<?SIWEBackupSecrets>,
 };
 
 const RegistrationContext: React.Context<?RegistrationContextType> =
diff --git a/native/account/registration/siwe-backup-message-creation.react.js b/native/account/registration/siwe-backup-message-creation.react.js
--- a/native/account/registration/siwe-backup-message-creation.react.js
+++ b/native/account/registration/siwe-backup-message-creation.react.js
@@ -1,5 +1,6 @@
 // @flow
 
+import invariant from 'invariant';
 import * as React from 'react';
 import { Text } from 'react-native';
 
@@ -9,6 +10,7 @@
 import RegistrationButton from './registration-button.react.js';
 import RegistrationContainer from './registration-container.react.js';
 import RegistrationContentContainer from './registration-content-container.react.js';
+import { RegistrationContext } from './registration-context.js';
 import { type RegistrationNavigationProp } from './registration-navigator.react.js';
 import type {
   CoolOrNerdMode,
@@ -68,15 +70,23 @@
     [panelState],
   );
 
+  const registrationContext = React.useContext(RegistrationContext);
+  invariant(registrationContext, 'registrationContext should be set');
+  const { setSIWEBackupSecrets } = registrationContext;
+
   const onSuccessfulWalletSignature = React.useCallback(
     async (result: SIWEResult) => {
-      console.log(result);
+      const { message, signature } = result;
+      setSIWEBackupSecrets({
+        message,
+        signature,
+      });
       navigate<'RegistrationTerms'>({
         name: RegistrationTermsRouteName,
         params,
       });
     },
-    [navigate, params],
+    [navigate, params, setSIWEBackupSecrets],
   );
 
   let siwePanel;