diff --git a/.idea/kotlinc.xml b/.idea/kotlinc.xml
index b1077fbd..0fc31131 100644
--- a/.idea/kotlinc.xml
+++ b/.idea/kotlinc.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="1.7.10" />
+    <option name="version" value="1.8.10" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
index 704c883b..0ad17cbd 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ExternalStorageConfigurationManager" enabled="true" />
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="Android Studio default JDK" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="jbr-17" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/build/classes" />
   </component>
   <component name="ProjectType">
diff --git a/forage-android/src/main/java/com/joinforage/forage/android/network/OkHttpClientBuilder.kt b/forage-android/src/main/java/com/joinforage/forage/android/network/OkHttpClientBuilder.kt
index 4144309c..a73c7fdd 100644
--- a/forage-android/src/main/java/com/joinforage/forage/android/network/OkHttpClientBuilder.kt
+++ b/forage-android/src/main/java/com/joinforage/forage/android/network/OkHttpClientBuilder.kt
@@ -18,7 +18,19 @@ internal object OkHttpClientBuilder {
                         .addHeader(
                             ForageConstants.Headers.AUTHORIZATION,
                             "${ForageConstants.Headers.BEARER} $sessionToken"
-                        ).run {
+                        )
+                        .run {
+                            // If the API_VERSION header has already been appended, don't override it!
+                            chain.request().headers[ForageConstants.Headers.API_VERSION]?.let {
+                                this
+                            }
+                                // Otherwise, set the default API_VERSION header
+                                ?: addHeader(
+                                    ForageConstants.Headers.API_VERSION,
+                                    "default"
+                                )
+                        }
+                        .run {
                             merchantId?.let {
                                 addHeader(
                                     ForageConstants.Headers.MERCHANT_ACCOUNT,
diff --git a/forage-android/src/main/java/com/joinforage/forage/android/vault/AbstractVaultSubmitter.kt b/forage-android/src/main/java/com/joinforage/forage/android/vault/AbstractVaultSubmitter.kt
index 383dcdc5..0dcdde3c 100644
--- a/forage-android/src/main/java/com/joinforage/forage/android/vault/AbstractVaultSubmitter.kt
+++ b/forage-android/src/main/java/com/joinforage/forage/android/vault/AbstractVaultSubmitter.kt
@@ -131,6 +131,7 @@ internal abstract class AbstractVaultSubmitter<VaultResponse>(
         .setHeader(ForageConstants.Headers.MERCHANT_ACCOUNT, params.merchantId)
         .setHeader(ForageConstants.Headers.IDEMPOTENCY_KEY, params.idempotencyKey)
         .setHeader(ForageConstants.Headers.TRACE_ID, logger.getTraceIdValue())
+        .setHeader(ForageConstants.Headers.API_VERSION, "default")
         .setToken(vaultToken)
 
     // PaymentMethod.card.token is in the comma-separated format <vgs-token>,<basis-theory-token>,<forage-token>