diff --git a/server/csp.js b/server/csp.js
index 5d24c602..c13ff44c 100644
--- a/server/csp.js
+++ b/server/csp.js
@@ -7,6 +7,7 @@ const unsafeEval = "'unsafe-eval'";
 const data = 'data:';
 const blob = 'blob:';
 const devImagesMaybe = dev ? ['*.localhost:8000'] : [];
+const baseUrl = process.env.REACT_APP_SHARETRIBE_SDK_BASE_URL || 'https://flex-api.sharetribe.com';
 
 // Default CSP whitelist.
 //
@@ -18,7 +19,7 @@ const defaultDirectives = {
   childSrc: [blob],
   connectSrc: [
     self,
-    process.env.REACT_APP_SHARETRIBE_SDK_BASE_URL,
+    baseUrl,
     'maps.googleapis.com',
     '*.tiles.mapbox.com',
     'api.mapbox.com',
diff --git a/server/index.js b/server/index.js
index ae4992e0..f45d5f7b 100644
--- a/server/index.js
+++ b/server/index.js
@@ -167,10 +167,11 @@ app.get('*', (req, res) => {
     secure: USING_SSL,
   });
 
+  const baseUrl = BASE_URL ? { baseUrl: BASE_URL } : {};
+
   const sdk = sharetribeSdk.createInstance({
     transitVerbose: TRANSIT_VERBOSE,
     clientId: CLIENT_ID,
-    baseUrl: BASE_URL,
     httpAgent: httpAgent,
     httpsAgent: httpsAgent,
     tokenStore,
@@ -182,6 +183,7 @@ app.get('*', (req, res) => {
         reader: v => new Decimal(v.value),
       },
     ],
+    ...baseUrl,
   });
 
   // Until we have a better plan for caching dynamic content and we
diff --git a/src/index.js b/src/index.js
index 9c0a3d05..3f856b08 100644
--- a/src/index.js
+++ b/src/index.js
@@ -77,13 +77,14 @@ if (typeof window !== 'undefined') {
   // set up logger with Sentry DSN client key and environment
   log.setup();
 
+  const baseUrl = config.sdk.baseUrl ? { baseUrl: config.sdk.baseUrl } : {};
+
   // eslint-disable-next-line no-underscore-dangle
   const preloadedState = window.__PRELOADED_STATE__ || '{}';
   const initialState = JSON.parse(preloadedState, sdkTypes.reviver);
   const sdk = createInstance({
     transitVerbose: config.sdk.transitVerbose,
     clientId: config.sdk.clientId,
-    baseUrl: config.sdk.baseUrl,
     secure: config.usingSSL,
     typeHandlers: [
       {
@@ -93,6 +94,7 @@ if (typeof window !== 'undefined') {
         reader: v => new Decimal(v.value),
       },
     ],
+    ...baseUrl,
   });
   const analyticsHandlers = setupAnalyticsHandlers();
   const store = configureStore(initialState, sdk, analyticsHandlers);