Microsoft will release Internet Explorer 9 on 14 March, while Mozilla has signed off on the release candidate for Firefox 4.
The release candidate for IE9 arrived last month, after a series of developer previews, but Microsoft suggested there were "still a few surprises left".
"There are a lot of new amazing things to share," said IE senior director Ryan Gavin, in a post on the IE blog.
The Monday release coincides with the start of the SXSW festival in Austin, Texas.
Meanwhile, Mozilla developers said the first release candidate for Firefox 4 would arrive either today or tomorrow, as soon as quality assurance (QA) checks were finished.
That's already happened this afternoon, according to developer Asa Dotzler on Twitter: "QA just signed off on Firefox 4 release candidate builds".
In notes from a Firefox delivery meeting today, Mozilla reported that there would likely be no need for a second release candidate - good news given the browser has seen 12 betas and is already trailing rival IE by a few weeks.
"QA has requested more time for thorough testing, so expect at least one to two more weeks before final ship," the meeting notes said.
Google today released the latest Chrome browser, as part of its six-week update cycle.