MailMerge365

MailMerge365 is a mail merge add-in for Microsoft 365 and Outlook. It sends personalized mass email from your own mailbox: you write the message in Outlook, upload a spreadsheet of recipients, add personalization tokens, and the add-in sends one individual email to each person, with optional open and click tracking, follow-ups and unsubscribe management. The homepage headline is "Send personalized mass email from Outlook & Microsoft 365," with the promise "Email that feels personal to them, yet automated for you!" It is built for people who already live in Outlook and want to send a few hundred or a few thousand personal-looking emails, whether cold outreach, customer updates or a message to every parent in a school, without moving to a separate campaign platform. The product is made by Sol Inventum OÜ, which the About page describes as "a fully remote company based in Estonia but working from offices around the world," with its corporate address in Tallinn.

What a sender actually gets

Works inside Outlook. The add-in is "Built for Microsoft 365" and works in Outlook on the Web, Outlook for Windows and Outlook for Mac. You can install it from Microsoft AppSource or start a trial from the site. Because you write the email in Outlook itself, you keep the editor you already use, "including adding attachments, images and signatures," as the features list puts it. There is no separate template builder to learn.

Spreadsheet personalization. A campaign starts from a spreadsheet in XLS, XLSX or CSV format. The site says you can personalize each email "by adding first and last names, company names, countries, a personal note or any other information you provide." You place personalization tokens in the email, and each recipient gets a version with their own data filled in.

Sent from your own account. Every email goes out from your personal mailbox rather than a shared sending service. The homepage argues this is the point of the product: mail from your personal account is, in its words, less prone to land in spam or promotional folders, and because each message reads as one you wrote yourself, it says "your response rates will skyrocket." A "Send As" feature lets you send from any of your mailbox's alias addresses.

Tracking and reports. Tracking is optional. When you switch it on, the site says you get "reports on who opened or forwarded your e-mail, which links were clicked and who replied to you." A dashboard shows which campaigns are sending and their main results, and detailed campaign reports show opened emails and clicked links. The add-in also detects bounces and unsubscribers automatically. Reports give a live view of performance with exportable data, and several reviews on the homepage mention downloading an Excel sheet with the current status of every recipient.

Follow-ups. You can "Send a follow-up only to those recipients that didn't respond or clicked on a particular link." One reviewer highlights following up "with a click of button with all of those prospects who opened or clicked on your email." This is a simple two-step pattern, not a multi-step automation builder.

Scheduling and sending limits. Campaigns can be scheduled: "Set a date and time for your newsletter to be sent and arrive at the right time for your target audience." Large sends are paced for you. The features list says "Campaigns are distributed over days if they go to a lot of recipients to be respectful of Office365 limits."

Unsubscribes. You can "Optionally add and manage an unsubscribe option to keep recipients happy," and unsubscribers are tracked and managed on every plan, including the trial.

Plans and pricing

The pricing section offers "Subscription for regular use or pay-as-you-go for occasional users," in three options:

• Trial, free, to send to 100 recipients, with open and click tracking, unsubscriber management and XLS/XLSX/CSV data sources. The closing call to action says you can "Install for free from the Microsoft Office Store and send to your first 100 recipients."
• Annual Subscription, priced per mailbox, with a maximum of 5000 sent emails per 24 hours, open and click tracking, unsubscriber management, spreadsheet data sources, no MailMerge365 footer added to your emails, premium support, and reports accessible for 1 year after sending.
• Pay as you go, to send to 1000 recipients one time, with the same tracking, unsubscribe and data-source features, no footer, premium support and one year of report access.

The homepage shows no price figures for the subscription or the pay-as-you-go pack. It does spell out the sending limits that sit above any plan: "all plans are subject to limits of Microsoft 365 (including their terms of service), any limits the administrator of your organisation has set and any limits the recipient's organisation has set. The maximum number of emails per day any single mailbox can send it limited to 5.000." In other words, the ceiling on volume is Microsoft's, and a large list will take several days to go out from one mailbox. The trial being limited to 100 recipients means it is a test, not a free plan. The footer links a refund policy, privacy policy and terms of service.

Support and reputation

Help runs through a help site with documentation, tutorials and frequently asked questions, which also hosts the support system for contacting the team. The homepage FAQ lists questions on requirements, trials, attachments and inline images, where data is processed, and whether your domain risks being flagged for spam. The About page carries a note from the founder: "Too often software grows complex and forgets about the humans that use it. I love to build products that seem simple on the surface but hide an incredible amount of thought and care."

The homepage shows a "5.0 on the Microsoft App Store" rating and a set of reviews. They return to the same points: time saved compared with Word's mail merge ("It's quicker, easier to use and train employees compared to the standard Word Mail Merge tools"), support that answers quickly, and the tracking plus follow-up combination. One reviewer says that at the start of the lockdowns they needed "to reach all (a couple of thousands) students/parents quickly to deliver personalized information," and that "support was outstanding. It even get enhanced with some of our suggestions." Another reviewer says they tried at least 15 other email tools before settling on this one because it works within Office 365.

Who it suits

MailMerge365 suits anyone in a Microsoft 365 organization who needs to send personal-looking bulk email from their own Outlook address: a salesperson doing low-volume cold outreach, an account manager writing to every client, a school or association contacting members, a small business announcing something to its customer list. The per-mailbox subscription fits regular senders, and the one-time pack of 1000 recipients fits someone who sends a mailing a few times a year. Because email goes from your own mailbox, replies arrive in your normal inbox.

It is not a marketing automation platform. There are no signup forms, segments or multi-step sequences on the site, and volume is capped by Microsoft's per-mailbox limit, so it is best for personal-scale sending rather than large newsletter programs.