Microsoft has quietly raised prices of Office for the Mac as much as 17% and stopped selling multi-license packages of the application suite.

The move puts Office for Mac 2011 on the same pricing schedule as the new Office 2013 for Windows. The price increases and the disappearance of the multi-license bundles also makes Microsoft's Office 365, a software-by-subscription deal the company has aggressively pushed, more competitive with traditional "perpetual" licenses.

It's not clear when Microsoft raised prices. The oldest search engine cache Computerworld found with the new prices was Feb. 2, so the company boosted them before then, likely on Jan. 29, the day it launched Office 2013 and Office 365 Home Premium. Microsoft did not mention the changes to Office for Mac in its press releases that day, or otherwise publicize the move on its Mac-specific website.

The single-license Office for Mac Home & Student now costs $140, a 17% increase from the previous price of $120. Office for Mac Home & Business, an edition that adds the Outlook email client to Home & Student's Excel, PowerPoint and Word, runs $220, or 10% higher than the older $200 price.

The new prices are identical to those of Office 2013 for Windows, as are the percentage increases.

Microsoft has also disposed of the multi-license editions it once sold: A three-license package of Home & Student that cost $150, and a two-license bundle of Home & Business priced at $250. To buy three licenses of Home & Student would now cost a customer $420, a 180% increase, while two licenses of Home & Business would run $440, or 76% more than the missing multi-license bundle.

The price increases and the killing of the multi-license packs were clearly intended to steer consumers and small businesses to a pair of Office 365 subscription plans.

Office 365 Home Premium, which costs $100 annually or $10 per month, provides a single household license that lets subscribers install Office for Mac Home & Business -- the one that includes Outlook -- on up to five Macs; install Office 2013 on up to five Windows machines; or install any combination of Office on five PCs and Macs. Home Premium launched Jan. 29.

Office 365 Small Business Premium, which will run $150 per user per year, allows up to five installations of Office for Mac Home & Business and/or Office 2013 on devices owned by one employer. To equip a three-person firm with Office using the subscription method will thus cost the business $450 per year. Small Business Premium is set to debut Feb. 27.

If Microsoft had not raised the prices of Office for Mac and eliminated the multi-license offerings, number-crunching customers would have realized that the subscription plan was no bargain in many scenarios.

But the higher prices of the perpetual licenses -- the traditional buy-once-use-forever form of Office for Mac -- make Office 365 the better deal when deploying four or five of the allowed copies.

Microsoft faced the same pricing dilemma with Office 2010 on Windows, and raised prices of Office 2013 licenses to make them less appetizing when compared to the Office 365 "rent-not-own" plan.

Buyers can still find Office for Mac 2011 at the older, lower prices, however. Although Microsoft has boosted prices on its online store -- as has Apple's e-store, which also sells the suite -- other retailers have not joined them. Yet.

As of late Sunday, for example, Amazon.com listed Office for Mac 2011 for as little as $116 in a one-license download format, and for an even-lower $109 in the three-license "family pack" edition. Amazon.com's price for a single license of Office for Mac Home & Business was $176.

Office for Mac 2011's new, higher pricing makes Office 365 plans more attractive: If customers install four or five of the allowed five copies of Office, the 'rent-not-buy' Office 365 plans are a better deal.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is gkeizer@computerworld.com.

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