Microsoft’s Office Insider for Mac is advancing nicely, and as part of the program, the company has released the very first 64-bit version of the productivity suite for the Apple platform.

Cupertino has always supported the transition to 64-bit versions of software released for its platforms, so it’s kind of weird to see Microsoft so late to the party, but a complex solution such as the Office productivity suite requires more time to get everything working smoothly in full 64-bit.

Microsoft announced the change this week and said that customers who aren’t using any add-ins in Office shouldn’t be affected in any way while those who rely on add-ins need to install their 64-bit versions.

“As you may know, Apple has long encouraged application developers to adopt the 64-bit runtime environment, and we’ve been hearing from customers (e.g. here and here) that 64-bit versions of Mac Office are desirable to enable larger address spaces, better performance, and new innovative features,” Microsoft announced today.

Only part of the Insider program

For the moment, these 64-bit versions of Word, Excel, PowerPoint, and Outlook are only part of the Insider program, but depending on how well testing goes and on the feedback the company receives in the coming weeks, it shouldn’t take too long before retail users get them too.

The first version that brings full 64-bit support is 15.25, so if you’re an Office Insider, this is the version you should be looking for. On Windows, 64-bit versions of Office have been around for a while, so it’s clearly good news that this transition is finally happening on Mac too.

The Office Insider program is available for any interested user, and preview builds of the productivity suite can be downloaded free of charge. They do come with some bugs because these are the risks of running pre-release software, but insider programs are a neat way to get access to new software before everyone else. Of course, such software shouldn’t be installed on production machines by any means.