According to Apple's System Status webpage, the service outage lasted from 3:35 p.m. to 4:11 p.m. Eastern and affected 30 percent of all iMessage users. That number was changed shortly after, with the notification saying "some" users were affected.
The brief interruption is the latest in a string of troubles for Apple's iCloud, which in June saw back-to-back outages affect 20 percent of users across multiple services, including iTunes Store purchases.
In April, a spate of issues hit iCloud email, GameCenter and iTunes, with Mail seeing downtime of 27 hours.
While Apple offers transparency in reporting when outages occur, the company rarely divulges causes. A contributor could be the massive amount of users attached to the service, which in March accounted for 27 percent of all cloud customers in the U.S., the most out of any service.
To deal with the rapid adoption rate, Apple is building out its cloud server infrastructure with a large datacenter in Reno, Nevada. On Monday, AppleInsider reported that the first structures were going up at the project site, which will ring up some $16 million in construction costs alone.