USGBC Review timeline

The GBCI usually completes design and construction reviews with with 6 weeks or less.  They may respond with some preliminary questions much sooner.  It is normal for them to ask for clarifications and additional information with the formal review. 

I haven't specifically tried to look up that info in the Reference books in a long time, but it was called out at some point (LEED v2009?) that they had "25 business days" to process it - which amounts to 5 weeks.  The only time I have ever experienced something more was around Christmas/end of the year, and that was years ago.  People would cram to submit their projects for review by the end of the year, and review staff was probably a bit reduced due to the holiday.  But I haven't had that happen in years.   Once you submit for review, and payment has been cleared, they will provide you a projected due date for the review response to be returned to you.  I believe that is still being calculated at 25 business days from cleared payment.

Their current review response time is 20-25 days.  I often experience sooner returns, however, their Guidance for Certification, available at https://www.usgbc.org/tools/leed-certification/commercial does identify the 20-20-25 day timeline. And, Renee is correct.  After payment has cleared, an anticipated review return date is calculated under the Timeline tab on LEED Online.