diff --git a/.env.example b/.env.example
index 4573bd6d..ca630513 100644
--- a/.env.example
+++ b/.env.example
@@ -17,6 +17,9 @@ SESSION_SECRET=change-this-to-a-random-string
 # Admin email (user with this email gets admin privileges)
 ADMIN_EMAIL=scott.mccarty@gmail.com
 
+# Newsletter sends (set to false for dev/test to avoid duplicate Buttondown emails)
+NEWSLETTER_SEND_ENABLED=false
+
 # Test environment (set automatically by vitest.config.js)
 # NODE_ENV=test
 # BYPASS_AUTH=true
diff --git a/backend/services/buttondownClient.js b/backend/services/buttondownClient.js
index c78e3267..a45a84a5 100644
--- a/backend/services/buttondownClient.js
+++ b/backend/services/buttondownClient.js
@@ -2,6 +2,10 @@ import axios from 'axios';
 
 const BUTTONDOWN_API_BASE = 'https://api.buttondown.email';
 
+function isSendEnabled() {
+  return process.env.NEWSLETTER_SEND_ENABLED !== 'false';
+}
+
 let apiKeyCache = null;
 
 async function getApiKey(pool) {
@@ -82,6 +86,11 @@ async function retryRequest(requestFn, maxRetries = 3) {
 }
 
 export async function addSubscriber(email, pool = null) {
+  if (!isSendEnabled()) {
+    console.log('Newsletter send disabled (NEWSLETTER_SEND_ENABLED=false), skipping addSubscriber');
+    return { email, status: 'send_disabled', skipped: true };
+  }
+
   const apiKey = await getApiKey(pool);
   const client = createClient(apiKey);
 
@@ -141,6 +150,11 @@ export async function getSubscriberCount(pool = null) {
 }
 
 export async function sendEmail(subject, htmlBody, pool = null, { existingEmailId, onDraftCreated } = {}) {
+  if (!isSendEnabled()) {
+    console.log('Newsletter send disabled (NEWSLETTER_SEND_ENABLED=false), skipping sendEmail');
+    return { skipped: true, reason: 'send_disabled' };
+  }
+
   const apiKey = await getApiKey(pool);
 
   let emailId;
@@ -205,6 +219,11 @@ export async function sendEmail(subject, htmlBody, pool = null, { existingEmailI
 }
 
 export async function sendDraftToRecipients(subject, htmlBody, recipients, pool = null) {
+  if (!isSendEnabled()) {
+    console.log('Newsletter send disabled (NEWSLETTER_SEND_ENABLED=false), skipping sendDraftToRecipients');
+    return { emailId: null, skipped: true, reason: 'send_disabled' };
+  }
+
   const apiKey = await getApiKey(pool);
   const client = createClient(apiKey);
 
diff --git a/run.sh b/run.sh
index 8aa63edf..58a25049 100755
--- a/run.sh
+++ b/run.sh
@@ -37,6 +37,7 @@ ENV_ARGS=""
 [ -n "$PGUSER" ] && ENV_ARGS="$ENV_ARGS -e PGUSER=$PGUSER"
 [ -n "$PGPASSWORD" ] && ENV_ARGS="$ENV_ARGS -e PGPASSWORD=$PGPASSWORD"
 [ -n "$PGDATABASE" ] && ENV_ARGS="$ENV_ARGS -e PGDATABASE=$PGDATABASE"
+[ -n "$NEWSLETTER_SEND_ENABLED" ] && ENV_ARGS="$ENV_ARGS -e NEWSLETTER_SEND_ENABLED=$NEWSLETTER_SEND_ENABLED"
 
 case "${1:-help}" in
     build-base)
@@ -165,6 +166,7 @@ MCP_ADMIN_TOKEN=$MCP_ADMIN_TOKEN
 PGUSER=${PGUSER:-postgres}
 PGPASSWORD=${PGPASSWORD:-rotv}
 PGDATABASE=${PGDATABASE:-rotv}
+NEWSLETTER_SEND_ENABLED=${NEWSLETTER_SEND_ENABLED:-false}
 ENVFILE
         fi