OutMass
OutMass is a browser extension for Chrome and Edge that adds mass-email and mail-merge capability to Outlook on the web. Campaigns are built inside Outlook itself, and every message is sent through the user's own Microsoft account via the official Graph API, so recipients see a normal email rather than a bulk sender. Microsoft 365 and personal Outlook accounts are both supported. Campaigns start from a CSV: each column becomes a merge tag, and every recipient gets a personalized message. Open and click tracking show who engaged, and a daily reply check catches responses. Automated follow-ups re-contact non-openers and stop the moment someone replies. Scheduled sending, per-day send limits, A/B subject testing, an AI email writer, reusable templates, campaign reports with CSV export, unsubscribe links and OneDrive-link attachments complete the toolset. The interface is available in 13 languages. Free plan: 250 emails per month. Starter: $9/month for 2,500. Pro: $19/month for 10,000.
Learn more
Yet Another Mail Merge (YAMM)
Send mass emails with Gmail. Reach the primary inbox, not promotion tab or spam. Track results in real-time directly from Google Sheets. Don’t waste time sending individual email messages. Create and send mail merge campaigns directly from Gmail with Yet Another Mail Merge (YAMM). Create your Google Sheets with your mailing list. You can even automatically import contacts from Google Contacts. Choose an email template, create a draft, write your content and subject line, add personalization, and save it. Return to Google Sheets, open Yet Another Mail Merge, and send. You'll be able to track email open rates, clicks, replies, and bounces to know what to send next. Easily send personalized email campaigns from Gmail. Create a message in Gmail (you can use saved Gmail templates). Send and track it from a Google Sheet. Personalize subject lines, email body, links, images and attachments to make your emails as convincing as possible.
Learn more
SecureMailMerge
The privacy focused mail merge add-in for Outlook and Microsoft 365.
Send marketing campaigns or confidential internal newsletters with the same tool. Your data never gets uploaded to any servers like with other tools, therefore stays safe with you at all time. The emails are sent from your own email address as if you sent them personally, so you get terrific response rates from people.
Use Outlook to write your formatted template email, add some personalization tokens from a spreadsheet or your address book, add any number of attachments and images and then watch as SecureMailMerge generates your emails for you right in front of your eyes.
Works on Windows, Mac and Browser versions of Outlook 365 and requires a Microsoft 365 Business subscription. Has support for Shared Mailboxes.
Learn more
MailMerge365
MailMerge365 lets you send mass mail through Microsoft 365. Campaigns are sent through your own Microsoft 365 business mailbox ensuring the best deliverability and response rates as each email looks like you crafted it yourself and is less likely to go into the promotional tab.
It allows users to create email campaigns from Outlook, connect to spreadsheets to personalize them, track opened emails, links and response rates, automatically detect unsubscribes and bounces, schedule campaigns, follow up with non-responders and view reports. It caters to professionals like fundraisers, recruiters and founders.
Learn more